Stephen Mlinae, age 13, Of Pittsburgh, Pa., for his question:

What is the Rosetta Stone?

Until about 200 years ago, no one knew the language of the ancient Egyptians. Plenty of papyrus scrolls had been found and plenty of words carved on stone, but no one could decode them. Then in 1799, the Rosetta Stone was found, and the whole problem was solved. It is a black tablet with the same text carved in three different languages.

At the top is the text carved in the picture writing of ancient Egypt. Below it, the same text is translated in Demonic, which was the everyday language of ancient Egypt. At the bottarn, the text is translated into Greek, a language which modern scholars can understand. They used the Greek text as a key to decode the two older languages.