Mike McClure, age 13, of Haggerstown, Md., for his question:

WHAT POWERS A SNOWMOBILE?

A snowmobile is a motorized sled that can carry one or two people over snow and ice. The first ones built in mass production were made by Joseph Armand Bombardier of Valcourt, Quebec, Canada in the late 1950s.

Powering the snowmobile is a gasoline engine that may vary from eight to 60 horsepower. On the front are two short skis and on the rear of the vehicle is a wide track or belt. The engine moves the track, propelling the snowmobile forward.

A snowmobile is steered with handlebars. Many snowmobiles can travel 50 miles per hour and some even faster. Rules of safety must be observed by all snowmobile operators.

Many environmental groups criticize snowmobiling because they say it destroys trees and shrubs under the snow. They also feel the vehicles endanger wildlife and provide a sound that disturbs the peacefulness of rural areas. To overcome the last charge, some manufacturers have produced quiet models.