Mary Alice Lanham, age 11, of Fargo, N.D., for her question:

HOW MANY POUNDS IN A TON?

There are three different ton units used to measure weight and capacity. They are the long ton, the short ton and the metric ton.

The long ton and the short ton are the two units most often used in the United States, but the metric ton is used by nearly all other countries.

The long ton equals 2,240 pounds.

The short ton equals 2,000 pounds.

The metric ton equals 1,000 kilograms, or 2,204.6 pounds.

United States customhouses use the long ton in weighing. Coal and iron ore are weighed and sold at the mines by the long ton and are sold by the short ton to customers.