Today's question:

The other day, President-elect Barack Obama had lunch at the White House with President Bush and three former presidents still living. Is this the most living presidents we have had? Nope, not even close. The largest number of living presidents over time has been six, if you count the sitting presidents, too.

This has happened three times.

I suppose you want the details. They're kind of boring, but here you go.

From March 1861 until Jan. 18, 1862, Presidents Martin Van Buren, John Tyler, Millard Fillmore, Franklin Pierce, James Buchanan and Abraham Lincoln were all with us.

From Jan. 20, 1993, through April 22, 1994, we had Presidents Richard Nixon, Gerald Ford, Jimmy Carter, Ronald Reagan, George H.W. Bush and Bill Clinton all hanging around.

And from Jan. 20, 2001, through June 4, 2004, we could still round up Presidents Ford, Carter, Reagan, George H.W. Bush, Clinton and George W. Bush.

There, I told you it was kind of boring.

Does cremation of cancer patients or of people who died of other diseases kill all of the disease present? People scatter their loved ones' ashes all over the place. Can we pick up a disease from cremated ashes?

Try not to worry about it.

If you die of cancer, the cancer dies with you. Your body just sort of shuts down, and the cancer cells shut down, too.

Even if something did linger on, which it doesn't, cremation would kill it - even anthrax spores or mad-cow stuff.

The sterile ashes left from a cremation are mostly just the dust of bones that have been exposed to extreme heat.

Reach Thompson at clay.thompson@arizonarepublic.com or 602-444-8612.