Kristen Morgan, age 15, of Gulfport, Miss., for her question:

HOW LARGE IS ARGENTINA'S PAMPAS?

Argentina's pampas covers about one fifth of the country's total area. It is a very fertile grassy plain that extends about 300 miles northwest, west and south of Buenos Aires. It covers about 300,000 square miles.

The word "pampa" comas from a Quechua Indian word meaning "plains." The pampas lies to the east of the Andean foothills and south of Argentina's dry, scrub Chaco region. It also extends to a treeless expanse in Paraguay, Uruguay and even into parts of southern Brazil.

Sloping upward very gradually, the pampas starts in the south at the coast. Its northern end is deep within the interior of the continent.

There are two parts of the pampas, each with its own type of climate. The western part is known as the dry pampas, while the moister eastern part is called the humid pampas. The humid pampas makes up what many experts consider the best farming area in all of South America.

At one time much of the dry and humid pampas was overgrown with monte, a covering of scrubby trees and coarse grasses. In the early 1500s when the Spanish arrived, they found the Indians burning the monte for purposes of warfare and hunting game. Because of these prolonged burnings, there has been a decrease in the woody vegetation and an expansion of grasses.

For more than 300 years, settlement of Argentina was only within the immediate area of Buenos Aires. Cattle ranching for production of hides, meat and tallow was the chief industry.

As time passed, cowboys called gauchos herded the cattle and fought with Indians in the vast back country.

Things started to change in the pampas in the middle of the 19th Century. The Indian tribes were pushed back and subdued sad the government sponsored immigration campaigns to encourage the settlement of the land.

Also changing the face of the land were the railways, which made it possible for goods to be shipped from the pampas to Buenos Aires' great port.

Three waves of settlers moved into the pampas after it was no longer dominated by the Indians. The first were the sheep ranchers who took over vast territories.

Then came the cattleman, who introduced alfalfa, which increased the grazing capacity of the land by about six tines.

The final wave was made up of crop growing farmers. They established large scale operations with farming colonies to provide the workers that were needed. Corn was one of the early major crops.

The population of the pampas was dominated by those with European backgrounds. The immigrants were mostly from Spain and Italy.

Cattle raising still is the chief source of income in the dry pampas to the west. In the eastern humid pampas, farmers grow much wheat, alfalfa, corn and flax.

Farmers near the urban centers grow fruit and vegetables.