2 - The only number with its letters in reverse alphabetical order.
3 - The only two people in the Baseball Hall of Fame who had nothing to do with baseball.
4 - The only person ever to decline a pulitzer Prize for fiction.
5 - The only brid able to fly backwards.
6 - The only continent without a desert.
7 - The only US state capital name that shares no letters with its state name.
8 - The only US state with just one syllable and borders only one state,
9 - The only continent home to wild camels.
10 - The only primates (other than human) that can have blue eyes.