On Jan. 1, Colorado became the first place anywhere in the world to allow legal marijuana sales to anybody over 21 for any purpose. You have questions about it works? Here are 64 answers (See what we did there? No? Keep reading.) to commonly asked questions.

Question: Did marijuana become legal in Colorado on Jan. 1, 2014?

Answer: Marijuana actually was legal in Colorado prior to 2014. Since the voter-approved Amendment 64 (ah, there it is) went into effect on Dec. 10, 2012, it has been legal for anyone 21 and over to use marijuana or possess up to an ounce of marijuana for any purpose — even if it is just, as Rolling Stone magazine has put it, “for getting high purposes.” Marijuana possession and use by people under 21 who aren’t medical-marijuana patients remains against the law.

Q: What happened on Jan. 1, then?

A: New Year’s Day was the first day that marijuana could be sold to anyone over 21 at specially licensed stores. Though marijuana use, possession and sales remain illegal under federal law, nowhere else in the world has pot sales this legal, not even Amsterdam.

Q: So, where can I buy weed?

A: More than than two dozen shops opened on Jan. 1 for recreational sales. We here at The Denver Post have compiled a list of stores that opened.

Q: How does it work?

A: Basically, you walk into a store, show your ID and make your purchase. It’s a lot like a liquor store.

Q: Where are the stores located?

A: The state has approved licenses for stores from Telluride to Alma to Garden City. But the vast majority of recreational marijuana stores, at least initially, are in Denver. Lots of other big cities — like Colorado Springs — have banned the stores. Other cities, including Boulder and Aurora, look likely to allow them but are going slow in setting the rules and accepting applications. Of the 136 stores that received state approval in the first wave of licenses to go out just before Christmas, 74 percent of them — 101 — are in Denver.

Q: Are there limited store hours?

A: Yes. Under state law, stores can’t open before 8 a.m. and they can’t stay open later than midnight. Cities, though, can set more restrictive store hours. In Denver, recreational marijuana shops can’t be open past 7 p.m.

Q: Are there limits to how much I can buy?

A: People with a Colorado ID can buy up to an ounce of marijuana at a time. People with an out-of-state ID can buy up to a quarter ounce.

Q: Was there enough pot to go around for recreational customers on Jan. 1?

A: There was, but some stores started running low pretty quickly. Commercial growing for recreational stores wasn’t legal until Jan. 1, either. So all the marijuana being sold to recreational customers on New Year’s Day came out of a one-time transfer from the stores’ medical-marijuana supply. Stores transferred plants over to their recreational sides as well — so they didn’t have to wait a full harvest cycle for more recreational bud — but they still faced a valley of supply before those transferred plants could be harvested.

For that reason, a lot of stores limited how much people could buy on Day 1 even beyond the limits in state law. Several stores also reported running out of marijuana-infused edible products, like brownies or candies, by Day 2. And a handful said they worried they might sell out of recreational pot altogether. Asked Thursday whether he had enough inventory to last until his next harvest, Northern Lights Cannabis Co. owner Mitch Woolhiser said, “If it keeps up like this, I don’t think so.”

Q: Can I make multiple purchases on the same day?

A: Yes. The only cap on how much you can buy is the legal possession limit: No one who is not a medical-marijuana patient can possess more than an ounce of marijuana at a time. But that’s up to the customer to abide by. There’s nothing in the state’s rules for recreational marijuana stores that requires them to track customer purchases.

Q: So I can go store-to-store-to-store buying up marijuana?

A: Yep. If you’re doing that with the hope of accumulating a lot of pot that you can sell in the black market, it’s known as “smurfing.” It’s illegal, and it’s something that law enforcement officials are super worried about.

Q: Is there any kind of list of marijuana customers that will be given to the government?

A: No. Amendment 64, which is a constitutional measure, specifically forbids it. The measure states: “The department shall not require a consumer to provide a retail marijuana store with personal information other than government-issued identification to determine the consumer’s age, and a retail marijuana store shall not be required to acquire and record personal information about consumers other than information typically acquired in a financial transaction conducted at a retail liquor store.”

Q: Is there anything that will show I bought weed at one of the stores?

A: You’ll be on camera. The state’s rules for marijuana stores require the shops to have a security camera pointed at the cash register so that it can record “the customer(s) and employee(s) facial features with sufficient clarity to determine identity.” Stores must also have security cameras recording the entrances and exits.

Q: Can I smoke up at the store?

A: No. On-site consumption is prohibited at marijuana shops. You have to take your leaves (or buds) and leave.

Q: So where can I go to consume? Are there cannabis clubs or coffee shops?

A: It’s a little fuzzy, but no. Some places may try to discreetly offer private areas where marijuana use is allowed or at least overlooked — like the Cannabition party wanted to do on Wednesday night at the Norad Dance Bar. But, under Colorado’s Clean Indoor Air Act, pot smoking isn’t allowed anywhere that cigarette smoking is also banned and there’s no cigar bar-style exemption for blunts.

Q: Can I just puff at a park somewhere?

A: Absolutely not. Public consumption is banned, banned, banned and probably prompts more anxiety from public officials than just about any other topic. Denver police have stepped up enforcement in the second half of 2013, though Denver did not have officers on Jan. 1 specifically tasked with stopping public toking. Boulder has upped its citations, too.

Q: Ski slope?

A: Ski nope. Colorado’s winter resorts are not at all stoked at the possibility of stoned skiers. And, what’s more, most of the actual ski slopes are on federal land, where marijuana use and possession remains strictly verboten.

Q: So that means taking marijuana on a summer camping trip is probably out, too?

A: Yes. National parks, national forests, national monuments: All off-limits. Possession is punishable by up to six months in jail and a $5,000 fine.

Q: What about apartments?

A: Landlords can say no. But what all of this is getting at is that the only place it’s clearly OK to consume is in a private residence where the owner is cool with it.

Q: How about on my back patio, front porch or balcony?

A: Different cities will regulate this differently. Denver, for a time, even considered banning marijuana use that could be smelled by a neighbor, as well as bans on backyard, front-porch and apartment-balcony marijuana use. The city backed off on all of those, but that doesn’t mean they’re OK everywhere.

Q: Wait, Denver tried to regulate pot smell?

A: Oh, it still does investigate complaints about skunk funk, but it has to be a very strong marijuana odor for the city to take action. And how is that odor measured, you ask? By the Nasal Ranger, of course.

Q: Can I take marijuana with me on a plane?

A: No. Taking marijuana out-of-state is totally illegal, even if you’re traveling to another legal-marijuana state. The Transportation Security Administration may not turn your bags inside out looking for marijuana, but they don’t approve of it either. And marijuana possession is banned at Denver International Airport — even if you’re just there to pick up a friend.

Q: Can I send marijuana in the mail?

A: Mail = fail. The U.S. Postal Service not only doesn’t allow pot in the post, it has stepped up its efforts to find marijuana mail. People who send marijuana through the mail can face federal charges or asset-forfeiture cases.

Q: Tourists are coming to Colorado for the start of recreational sales, right?

A: At least three companies planned to offer marijuana tours on New Year’s Day, but nobody knows how big of a deal marijuana tourism will be. Certainly people will come for the cannabis. But state tourism officials are opposed to promoting Colorado as a hash holiday destination, and most resorts and hotels aren’t exactly embracing the idea either.

Q: So where will those tourists consume marijuana?

A: Hotels have the ability to allow — or turn a blind eye to — guests’ consumption. But Denver, for instance, prohibits marijuana consumption outdoors in areas of non-residential private property that are visible from a public space. So certain hotel balconies in the city are off-limits. Furthermore, the city’s marijuana info website notes that pot smoking could only be allowed indoors in designated smoking rooms, and hotels can’t have more than a quarter of their rooms designated as such. Still, word-of-mouth had gotten around about some hotels that would allow marijuana use, and they expected brisk business New Year’s Day.

Q: Is it OK to drive with marijuana in my car?

A: Yes, as long as you are transporting it and not consuming it. Driving stoned is absolutely against the law. In fact, Colorado this year made it easier to win convictions against stoned drivers. The state set a standard of how much THC, the psychoactive chemical in marijuana, that drivers can have in their system. If a driver tests above that, prosecutors can tell the jury it’s OK to assume that driver was stoned.

Q: Will my employer be OK with me using marijuana?

A: That’s really between you and your boss. Employers can pretty clearly fire people who show up to work baked. But Colorado case law around medical marijuana suggests they can also fire an employee for off-the-clock marijuana use, even if there’s no allegation that the employee was impaired on the job. Some businesses say they won’t mind if their workers get high on their own time, but as one lawyer put it, “Employers hold all the cards.”

Q: What about contact high? Could I be fired for being around someone using marijuana?

A: Likely not, for the simple reason that contact highs are really difficult to come by. According to a psychopharmacologist — real word, look it up — at the University of Colorado, it would take “an absurd amount” of secondhand pot smoke to trigger a positive test. One study showed there needs to be 14 joints burning in a 10-by-10 room to get a positive test for contact high, which is beyond all but the hottest of hotboxes.

Q: With all these caveats, I can legally possess an ounce of marijuana. How much is that in practical terms?

A: It’s a lot. Researchers have calculated that the average joint has slightly less than a half gram of marijuana. (Yes, this is actually something that people with Ph.D.s did.) An ounce is slightly more than 28 grams. So one ounce will get you close to 60 joints. In alcohol terms, it’s a keg of pot.

Q: And how much will it cost?

A: In the medical-marijuana market, ounces run from $150 to close to $300. But almost nobody buys full ounces. The more common purchase amount is an eighth of an ounce. Think of it like a 12-pack. Eighths run around $25 to $45 for medical marijuana. We’ll have to wait and see what stores set as the recreational prices.

Q: Does that include tax?

A: No, and get ready for the sticker shock when tax is added on. While medical marijuana purchases only get standard sales tax in most places, recreational marijuana purchases get standard sales tax, plus hefty special state sales and excise taxes, plus extra local sales and excise taxes in many cities. For a $30 eighth, state taxes will run about $6. Extra taxes in Denver will add on another $2.59. All together, that’s nearly 29 percent.

Q: Where’s all that money going?

A: The first $40 million generated by the state excise tax will go toward school construction. The rest of the money is slated to be used to regulate the marijuana stores and put together educational campaigns around marijuana. But many expect the revenue to exceed even those needs, and a number of cities have already begun dreaming about what their share of the tax money could do.

Q: Could recreational marijuana cause prices to drop?

A: Researchers have suggested that large-scale marijuana legalization would cause prices of pot to plummet. But, with all the rules stores must comply with in Colorado plus the uncertain demand for store-bought marijuana, it’s not clear what will happen to prices long-term in the state’s new marijuana market.

Q: Will recreational marijuana stores take credit cards?

A: It’s best to check with the shops. But, in general, legal marijuana shares this in common with black-market marijuana: It’s a cash business. Federal banking regulations mean that marijuana stores commonly don’t have access to banking services. There is a possible solution on the horizon, but, for now, expect to pay for green buds with greenbacks.

Q: Will the federal government put the kibosh on Colorado’s marijuana industry?

A: It certainly has the option to, but all signs are that it won’t. President Barack Obama has previously said — to Barbara Walters, no less — that the feds won’t arrest individual marijuana users in Colorado and Washington, the two states that have legalized pot use for people over 21. An August Justice Department memo tells federal prosecutors not to make it a priority to block marijuana-legalization laws or shut down marijuana stores abiding by state laws and regulations, as long as those rules are robust.

Q: Robust like how?

A: The Department of Justice has identified eight things it’s most concerned about that it wants state marijuana regulatory schemes to address. If those concerns are dealt with, the DOJ says in the memo it’s open to the possibility that states with legalized marijuana could replace “an illicit marijuana trade that funds criminal enterprises with a tightly regulated market in which revenues are tracked and accounted for.”

The eight federal priorities are:

• Preventing marijuana distribution to minors;

• Preventing money from sales from going to criminal groups;

• Preventing the diversion of marijuana from states where it is legal to states where it is illegal;

• Preventing criminal groups from using state laws as cover for trafficking of other illegal drugs;

• Preventing violence and the use of illegal firearms;

• Preventing drugged driving and marijuana-related public health problems;

• Preventing the growing of marijuana on public lands;

• Preventing marijuana possession or use on federal property.

Q: So how will Colorado regulate marijuana stores?

A: Hopefully more tightly than it has previously regulated medical-marijuana shops.

All people selling or commercially producing recreational marijuana need a license to do so. There are security specifications, limitations on where stores can advertise, prohibitions on who can work in the industry, packaging requirements, health-and-safety measures and dozens of other rules. There is also an ambitious seed-to-sale tracking system that will keep tabs on individual marijuana plants from the time they’re placed in soil to the time their products leave the store. The state rulebook for recreational marijuana stores stretches 136 pages long.

Q: Seed-to-sale tracking? How does that work?

A: In December, the state rolled out its $1.2 million marijuana-tracking system called MITS, for, uncreatively, Marijuana Inventory Tracking Solution. (Take a test drive for yourself here.)

It works like this: Every plant that a commercial grower sticks in dirt gets a radio-frequency tag that moves with the plant through its lifecycle. Once the marijuana is harvested, everything is weighed, then it’s weighed again after drying out and at other points during processing until it’s all packaged up to leave the grow. The packages shipped to the stores can’t weigh more than a pound and they get their own RFID tags. At the shop, store owners are required to weigh their inventory every day. All of this data is entered into MITS.

Stores are also required to have some type of point-of-sale tracking system to chart sales. In theory, every purchase in the point-of-sale system should have a corresponding drop in inventory in the marijuana-tracking system. It’s up to the state’s pot auditors to actually scour the books and make sure it all matches up.

The tracking system does have its limits, though, which is why officials say it is just an enforcement tool, not the whole regime. And, embarrassingly for the state, holiday shipping delays mean that not all plants in the commercial system were entered into MITS by Jan. 1.

Q: What are the packaging rules?

A: All pot leaving a recreational marijuana shop must be in an opaque, child-resistant package. All marijuana products also must have labels on them, detailing the potency, the types of chemicals used in cultivation and other information. And every label has to have the state’s official, incredibly dull-looking marijuana decal on it.

Q: How many people are on the job for the state?

A: The state Marijuana Enforcement Division is budgeted for 25 criminal investigators and six to eight compliance investigators. Considering that there will likely be hundreds of recreational marijuana stores, state officials say investigators will use the data in MITS as part of a risk-based enforcement approach, rather than making consistent, frequent checks at all stores, grows and infused-products businesses.

Q: Stores, grows, infused products-makers? What’s with all these different business types?

A: Stores are easy to explain — they sell pot. Infused-products businesses are the folks who make marijuana brownies and the like, but also things such as marijuana-infused drinks, tinctures to be used under the tongue, lozenges, balms and any number of other products. There’s even marijuana-infused massage oil.

The grows — or cultivation facilities, in state officials’ terms — are what supply marijuana to the businesses. Unlike in the world of Doonesbury, people off the street can’t just sell weed to licensed stores.

The state also issues licenses to people wanting to open marijuana-testing labs, which check marijuana for molds and toxic chemicals and also measure potency.

Q: So all these businesses work independent of one another?

A: Not currently. Like the state’s medical-marijuana industry, the recreational marijuana industry will start out vertically integrated. That means stores and grows have to be part of the same business and stores must grow almost everything they sell. There can be stand-alone infused-products makers, but they can’t sell their products to the public independently. That must be done through a store, too.

Q: I want to open my own marijuana store. Where do I start?

A: Unless you’re already in the Colorado marijuana business, you’ll need to bide your time for a bit. Until July, the only people who can apply to open a recreational marijuana store are those who are already licensed to run a medical-marijuana business. The earliest newcomers can open up shop is Oct. 1, 2014.

Q: And those newcomers will have to be vertically integrated businesses, too?

A: Nope. Starting in October, Colorado’s marijuana industry goes into a blender and the ties between growers and sellers can be chopped apart. Existing growers and sellers can decouple. New businesses can be stand-alone stores or wholesale growers. It will be a whole new model for the young industry — assuming the state legislature doesn’t change the plan in its 2014 session.

Q: Who are the owners of the first recreational marijuana stores?

A: It’s unclear because the state won’t yet release a list of owners — or even a list of stores that have applied. But all indications are that they are the same big players in the medical-marijuana industry. (For instance, Shawn Phillips, who records show has a stake in at least six medical-marijuana dispensaries in Colorado, was the first person to pick up a city license in Denver to sell recreational marijuana.)

Today, most of the major players in the medical-marijuana industry are people with serious business backgrounds, all the better to compete in an increasingly competitive marketplace.

Q: How much does it cost to open a marijuana store?

A: The state charges an application fee of $5,000 ($500 if the applicant currently owns a licensed medical-marijuana business) and license fees from $3,750 to $14,000. But that just makes you legal. The total startup cost for a marijuana shop — including all the necessary growing equipment, decor upgrades, security systems and real estate — is in the hundreds of thousands to millions of dollars. Most business owners get the money from their personal savings, friends and family. But specialized marijuana investment groups are also playing a bigger role. Currently, all money invested in Colorado marijuana businesses must come from people living in the state.

Q: Why do the license fees vary?

A: It’s based on how big your business is. The state has three tiers for both medical-marijuana dispensaries and recreational marijuana stores. On the medical side, the tiers are based on how many medical-marijuana patients are registered with the dispensary. The recreational tiers — at least initially — are built on plant counts. Type 1 stores, the smallest level, can grow up to 3,600 plants combined in its cultivation facilities. Type 2 shops can grow 6,000 plants. And Type 3 stores can grow a whopping 10,200 plants.

Q: Ten thousand plants? How much will that produce?

A: You’re walking down a rabbit hole, my friend. Debates over marijuana plant yields are epic. It depends on the growing method, the length of time, the fertilizers used, the lights used, the room conditions, the music you play to the plants, and just about every other variable you can imagine. Let’s just assume that standard indoor growing conditions will yield about 2 ounces per plant. That means 10,000 plants will get you a stupefying 1,250 pounds of sticky icky.

Q: If the feds decided to prosecute a store growing 10,000 plants, what would the punishment be?

A: Growing more than 1,000 marijuana plants is a minimum 10-year federal prison sentence and an individual fine of not more than $10 million. Trafficking 1,250 pounds — about 550 kilograms — comes with a five-year minimum prison sentence and up to a $5 million individual fine. So it’s little wonder why RiverRock dispensary owner Norton Arbelaez says pot shops have extra incentive to follow the state’s rules: “If you’re an irresponsible business owner in this business, you lose your freedom.”

Q: Other than having a lot of money, what requirements are there for marijuana business owners?

A: They must be Colorado residents — meaning they have to have lived here for two years. If they have been convicted of a felony, they have to wait five years before applying to open a store. And if that felony was drug-related, they must wait 10 years.

Q: How do I just get a job in the marijuana industry?

A: Try, try and try again. Sometimes job listings are posted on Craigslist or a website like Cannajobs.com. Sometimes stores advertise open positions on their own websites. There are several marijuana trade schools in Colorado.

If you do get hired, you’ll need an occupational license from the state. And that involves a complicated lottery process that could require several trips to the Marijuana Enforcement Division’s office.

Q: Why can’t I just grow my own marijuana at home?

A: You can. Colorado law allows people 21 and older to grow up to six plants, provided it’s done in an “enclosed, locked space.” Some cities have limited the number of plants that can be grown in a single house — Denver’s cap is 12 — and some cities have imposed other zoning or code restrictions on home-growing. Even without those hurdles, experts say that, just because it’s called weed, don’t expect marijuana to grow as easily as one at home. That difficulty is the main reason why the recreational marijuana stores are expected to be so popular.

Q: How many people are expected to shop in Colorado recreational marijuana stores in 2014?

A: It’s really anybody’s guess. The state’s nonpartisan voter guide — in estimating the revenues from marijuana tax measures — projected nearly $400 million a year in recreational marijuana sales. Considering that medical-marijuana stores, alone, did almost $330 million in sales in fiscal year 2013, that number might be low.

Q: What happens to the medical-marijuana industry now?

A: It’s still here. A number of places that allow medical-marijuana dispensaries — like Colorado Springs and Englewood — have banned recreational pot shops. Furthermore, the state still has a medical-marijuana registry of 112,000 people who are eligible to shop in medical dispensaries. That number may go down after recreational sales start, but it has actually increased since marijuana was legalized for everyone in the state.

Q: Why would anyone stay as a medical-marijuana patient?

A: If you’re buying marijuana regularly, there are some benefits. Medical-marijuana patients don’t pay the extra sales and excise taxes that are on recreational sales. And they can possess up to two ounces of marijuana — sometimes more, if their doctors recommend it — instead of the one ounce that regular adults get. What’s more, the state is looking at dropping its patient registry fee, to $15, which could tip the balance in favor of staying on the medical registry for more people. Plus, there will still be a market for people under 21 to buy medical marijuana.

Q: Kids can legally use medical marijuana?

A: Yes. There are some extra requirements for kids under 18 to become registered patients, but Colorado now has 128 registered medical-marijuana patients under 18. The state has seen an influx of families moving here to seek treatment for children with severe seizure disorders, after a family of brothers developed a non-psychoactive marijuana extract that parents say greatly reduces their children’s seizures.

Q: Are all the medical-marijuana dispensaries changing to recreational stores in places that allow them to?

A: No. There have actually been very few applications for a total conversion. Most stores are going recreational while keeping their medical sides, too. In Denver, if the stores agree only to sell to medical-marijuana patients over 21, it’s as simple as just keeping the books separate. Stores can also have an all-ages medical-marijuana side and a 21-and-over recreational marijuana side, so long as they build a wall between the two sides.

Q: Then what big impacts has the first step of marijuana legalization had on Colorado?

A: For the most part, it’s too soon to tell. Comprehensive numbers on use, emergency room visits, treatment admissions, and stoned driving are not yet available for 2013. The data there is shows it’s a mixed bag: The number of prosecutions for all marijuana crimes, especially minor marijuana crimes, plummeted — including for people under 21. But citations for public use of marijuana rose.

Q: Are schools seeing more problems with kids using marijuana?

A: In the 2012-13 school year, the state reported that 32 percent of the state’s expulsions were related to marijuana. But, because it’s the first time marijuana-specific numbers have been kept, it’s impossible to tell whether that amount is higher or lower than in previous years. And, because the numbers don’t reveal the precise infractions, it’s hard to gauge what kinds of problems schools are seeing. (Dropout numbers, for instance, are actually down.) But suspensions and expulsions for all drugs in Colorado schools have been rising, and education and law enforcement officials are increasingly concerned about marijuana at school.

Q: Do marijuana stores cause increases in crime?

A: It depends on what you consider an increase. Certainly there are more crimes being committed at marijuana stores compared to five years ago — if for no other reason than there are lots more stores. But police in Colorado have never demonstrated that marijuana businesses make their neighborhoods less safe. The slight increase in crime near medical-marijuana dispensaries in Denver in the first half of 2013 was in line with overall crime trends in the city. A three-year-old Denver police analysis showed that marijuana stores were robbed at a lower rate than banks.

Q: Is Colorado going to become a source state for black-market weed?

A: Some would say it already is. Law enforcement officials say marijuana is flying (and driving) out of Colorado like never before. In Oklahoma, officials say Colorado-grown pot has gained a special reputation for potency. And, because of the numerous legal ways there are to obtain marijuana in Colorado, law enforcement concerned about the problem say they have little hope of stopping the out-flow.

Q: State officials also worried that legal marijuana would hurt economic development efforts. Did it?

A: It doesn’t appear so. A state economic development official told a legislative committee in November that, “so far the information we get anecdotally is that it hasn’t impacted our ability to be competitive.” But, the official cautioned, he doesn’t know how many businesses didn’t even consider moving to Colorado because of the marijuana laws.

Q: Will legal marijuana sales lead to more people using pot in Colorado?

A: It seems likely but how much of an increase is up for debate. Studies have shown that states with medical-marijuana laws are likely to have higher rates of marijuana use. But that doesn’t mean there is more use because of the laws. It could be that states with already elevated use rates are more receptive to liberalizing their marijuana laws. Furthermore, some of the country’s leading drug-policy thinkers have shown that — as America’s marijuana laws have softened in recent years — the number of people using marijuana has increased some but the amount that heavy marijuana users consume has increased much more. So it’s possible that legalization won’t lead to a large ripple of new people sparking up but will instead entrench marijuana more strongly in the lives of those who already use.

Q: Would increases in marijuana use rates be a big problem for Colorado?

A: In the sense that increased use could lead to increases in stoned driving, marijuana at schools and marijuana dependence, yes. Treatment professionals report that their case loads are skyrocketing with legalization. “Inside of our treatment program, it is very rare to see someone who comes to us who doesn’t have marijuana as an issue,” said Ben Cort with the Colorado Center for Dependency, Addiction and Rehabilitation.

But there are other factors to take into consideration when evaluating the overall impact of legalization. If using marijuana more frequently causes people to consume less alcohol — and, thus, reduces alcohol-related problems — it could be a net win for Colorado, according to researchers like Mark A.R. Kleiman. If marijuana and alcohol are used together, it could compound the problems of both. It’s something we’ll just have to wait to find out.

Q: When will we actually have answers to all of these questions?

A: Both marijuana advocates and skeptics agree it will be years. Colorado Attorney General John Suthers says it will be at least a couple of years before clear answers arrive. Allen St. Pierre, the head of the national pro-marijuana group NORML, predicts it could take up to a decade. So, sit back Colorado. Like it or not, this is a long, strange trip we’re all on together.

John Ingold: 303-954-1068, jingold@denverpost.com or twitter.com/john_ingold

Update: Jan. 3, 2014 at 11:30 a.m. This story, originally published on Dec. 31, 2013, has been updated to reflect that the first day of recreational marijuana sales in Colorado has happened. Additionally, specific information to the question about whether retailers had enough pot on January 1, 2014 has been added.