Jeff Dunkel, age 13, of St. Paul, Minn., for his question:

HOW DID THE WORD "COP" ORIGINATE?

The word ''cop'' is an informal or slang name for a policeman. In the olden days, policemen wore copper buttons on their dark blue uniforms. Many people called an officer "copper" in an affectionate way, and the word was finally shortened to ''cop.''

A British statesman named Sir Robert Peel founded the London Metropolitan Police in 1829. The public called the officers bobbies, after Sir Robert, and the nickname is still used today.

The word sheriff is a shortened form of shire reeve, an expression that goes back to about 800 A.D. in England. At that time, law enforcement was based on citizen responsibility. When a young man reached the age of 16, he took his turn at standing watch. In each shire, or county, the citizens' law enforcement group was headed by a reeve, or chief.