Olyssa Munson, age 10, of San Diego, Calif., for her question:

WHO DISCOVERED THAT THERE ARE 60 MINUTES IN AN HOUR?

This wondrous story goes way back to the magi of ancient Babylon. Actually they were astronomers who studied the stars. To do this they needed numbers, math and circles. They invented a math system based on sixes and 60s. They used two sixes to get 12 and half of 60 to get 30. They used 12 30s to divide the circle into 360 equal degrees  or angles.

Much later, these circle divisions were used to create the 12 hours on the face of the clock. Each hour has 60 minutes and each minute has 60 seconds. The old magi of Babylon invented this system perhaps 5,000 years ago. And nobody has invented a better one.