What is the only 15 letter English word that can be spelled without repeating a letter?

In 1918, the US Postal Service began airmail service and since it would cost more than the regular first class 3 cents postage, they issued a 24 cent airmail stamp. The stamp showed a picture of the airplane that was going to carry airmail letters – a remodeled Curtiss Jenny JN-4HM. Since the stamp was printed in red and blue, in those days it had to be sent through the printing press twice – once for each color – and while they always tried to be careful when inserting the sheets for the second run, one incorrectly (inverted) sheet wasn’t noticed and was released. Eventually the sheet was broken into single stamps and sold to collectors at in 2016, at the New York Stamp Expo, one “Inverted Jenny” stamp was sold at auction for $1,175,000. That was the first US Postal Service inverted misprint.

The photograph shows the now-famous “CIA invert” stamp, an error in the one-dollar U.S. postage stamp. As you can see, the dark brown (the last color printed and which is the color of the lamp candle holder, candle outline and text) is inverted relative to the flame. The “CIA invert” was not the first (nor the last) stamp issued by the United States postal authorities that contained errors, nor is it the first to contain an inverted misprint. What was the first?

For those of you interested in the CIA invert story, one sheet of 100 is the subject of our story. Here is what we know: These $1 stamps were printed in sheets of 400 (each with 100 stamps), so we know 3 additional sheets must have existed at some point, but no trace of them has ever been uncovered. The ‘known’ sheet of 100 was sold at the McLean, Virginia post office. No one in the post office noticed the error and five were sold over the counter (and presumably used for postage). At some point, a CIA employee was sent to the post office to buy stamps for the agency and bought the remaining 95 stamps in the sheet. Again, the mistake wasn’t noticed until a few days later when another CIA employee needed a $1 stamp for postage and discovered the mistake. Sharing his find with eight of his CIA co-workers, they went to the post office, bought 95 correctly printed $1 stamps and exchanged them at the CIA for the misprints. At some point, it seems they decided to keep one stamp each and sell the rest. They contacted a stamp dealer who bought the remaining 85 as a block, together with 1 single that was damaged. The dealer tried to protect them, reporting that the 14 ‘unaccounted’ stamps in the sheet of 100 may have been inadvertently used by the CIA for postage. But once the story surfaced, the CIA started an investigation and ultimately demanded each of the employees either return the stamp they kept or be fired. Four of them did, four refused (and were fired) and one claimed he lost the stamp (and remained a CIA employee).

The athlete who received the most votes from American children as their hero in a 1976 Ladies’ Home Journal survey was O.J. Simpson.

In 1976, Ladies’ Home Journal asked American children to name their heroes. What athlete got the most votes?

The largest living structure on Earth is the Great Barrier Reef in Australia.