JERSEY CITY — Sandra Coronado is sitting in her SUV at a BP gas station on the corner of Communipaw and West Side avenues in Jersey City. It's around noon, but she's feeling sleepy when a man walks up to her and hands her $10.

"Is this for real?’’ Coronado exclaims.

Delores Jackson is thinking "con artist," as this strange person approaches. But he gives her $10 as well.

Ann Clayton is also getting fuel and her scam antennae goes up, too. She reluctantly holds onto the $10 bill he put in her hand, thinking, "What’s the catch?"

Nobody gives you something for nothing, right?

We know someone who does.

On this day, Jemmie Adams of Jersey City is giving people he doesn’t know $10 toward their gas bill. By the time he is done, he has kicked in $10 toward the gasoline bill for 28 strangers. $280. Why 28? We’ll get to that.

SEE COMPLETE LIST OF JEMMIE ADAMS’ ACTS OF KINDNESS HERE

A month ago, Adams decided he wanted to do something for others totally out of kindness, asking nothing in return. He wanted to give people gifts they would never dream of getting from a stranger.

"We are all connected,’’ he said. "When you show someone kindness, they can take that kindness and give it to someone else.’’

Adams works by his own special kindness math.

On Day One he fed one person. Day Two, it was two people. And that’s how the numbers grew with every outing, the acts of kindness ranging from lunch and dinners to bus fares to gas to whatever he could think of after leaving work as a manager at E-Commerce in Lyndhurst.

Valentine’s Day was Day 19 and that’s how many mothers received long-stem yellow roses and a box of chocolate at Hope House, an emergency shelter for women and children in Jersey City.

"It was beautiful,’’ said Lavette Pickett, a residential assistant at the shelter. "It’s the little things that add up."

Captain Do-Good has done something nice for 30 consecutive days. He chose 30, he says, since it takes about that long for anything you want to accomplish to become a habit. His cousin, Denise Goodson, has been along for the ride, recording this adventure.

"Once you fully and truly understand that we are all connected, you can work on relationships and the harmony we have between each other,’’ he said.

All told, Adams spread goodwill to more than 500 people, spending $1,500 of his own money.

When I first caught up to him, it was last Friday evening — Day 26.

We’re at the Journal Square Path train and bus station, and Adams gets on and off three buses to pay the $1.50 fare for 26 riders on their way home from work.

Monique McCall has the dollar, but was scrambling for change when Adams told her to put her money away.

"God bless him,’’ McCall said. "I think it’s wonderful.’’

Other’s tried to give him back the fare when he paid, but he wouldn’t accept it, telling them this ride was on him.

He was at it again the next day, Day 27, dropping off enough pizza pies at Jersey City Medical Center to feed 27 people, including nurses and families waiting in the emergency room. The pies flowed again Monday, Day 29, as a surprise for 29 workers at a tire center and a warehouse shipping department in Lyndhurst.

Ann Clayton of Jersey City, left, is skeptical at first when Jemmie Adams, right, offers to give her $10 towards her gas. Adams believes in helping people, so for 30 straight days Adams is doing acts of kindness for complete strangers.

Ray Sandoval, a tire center employee, said they didn’t know who sent them the food until they called the pizza place.

"There are still nice people in the world,’’ Sandoval said.

Just about everyone who meets him or learns about him is incredulous, like this can’t be happening. Some think he hit the lottery or that he’s with a charitable organization. He doesn’t say much about his generosity, only that his will is from the heart. Nothing more.

When the people see he’s for real, they let their guard down.

Jonathan Rodriguez of Brooklyn took the $10 gas gift on Day 28, shaking Adams’ hand for his friendly purpose.

"There’s not that many people who will do that,’’ he said. "I hope many good things come to him and his family.’’

Most of Adams’ time has been in Jersey City, but he’s been to Hoboken and Newark Penn Station, where he ended the tour Tuesday with hoagie sandwiches for the hungry. Aside from his penchant to help, Adams’ first love, he says, is writing, having authored the novel "Running With No Feet,’’ but what a tale this past month would be if he sits down to pen it.

While many are stunned by the benevolence, none of it surprises Talib Ahmad, a childhood friend since grade school.

Ahmad can still see Adams giving away neatly kept clothes he could no longer wear as a teenager. He laid them across the fence in their Jersey City neighborhood for anyone who needed them.

"He wants people to pick up on being kind to one another and establish that as the norm instead of it being odd.’’

It must be catching on.

Tom Revell was at the gas station, but he didn’t’ take the gas money. He could tell right away Adams was a genuine spirit.

"Give mine to the next person,’’ Revell said.

Adams smiled. That’s what he’s talking about.

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