21. Hydrogen the nine (A) most abundant element in the Earth's crust(B), is an(C) odorless, colorless, and tasteless(D) gas.

22. Salamanders are frequently (A) to be find(B) in moist(C), wooded(D) areas.

23. Steam engines have been replaced (A) in most(B) cases by(C) more economical and efficiency(D) devices, such as the electric motor.

24. Traditionally(A), the Fourth of July is celebrated(B) in the United States with political speeches, picnics, and most important of all(C), a displayed(D) of fireworks at night.

25. The style of used (A) in cartoon animation range from relatively(B) realistic representations of everyday life to the most romantic and impossible fantasy(D).

26. Ordinary(A) beaver dams vary(B) in length from a few feet(C) to a hundred feel ormore than(D).

27. In the United State, presidential elections(A) are held(B) once every(C) four year(D).

28.Except of (A) the freehand toe, the feet(B) of the(C) gull are fully(D) webbed.

29. Teaching machines are devices that can store instructionally(A) information,present displays, receive(B) responses from a learner(C), and act on those(D) responses.

30. Challotte Perkins Gilman Is known primarily (A) as an author of short(B) stories, but she also wrote an influential book argued(C) for equal(D) economic opportunities for women.

31. In some areas(A) of the United States, unfavorable climate or(B) soil make farming(C)an impossible(D) task.

32. Naturalists have identified(A) at least four hundred of species(B) of mammals andsix hundred types of birds(C) in the state of(D) California.

33. Instead of tooth(A), the blue whale has a row(B) of bony plates in its(C) mouththat functions as(D) a food-collecting device.

34. Murres are black-and-white driving(A) birds that mate every five or six years and lay(B) only a single(C) egg at time(D).

35. A bar code consists(A) a pattern of lines(B) and bars that(C) a computer can translateinto information(D).

36. Hummingbirds are(A) the only(B) birds(C) that can fly to backwards(D).

37. Fluorine, a greenish-yellow gas that is slightly heavy(A) than air is poisonous(B)and corrosive and has a penetrating and disagreeable(D) odor.

38. The Everglades, a large swamp area(A) is an(B) unique wilderness(C) extending over much(D) of southern Florida.

39. Each year(A) millions of tons(B) of fertile topsoil that could(C) produce good crops washed(D) away by rains.

40. Since the(A) 1950's, folk' music has had(B) a significant(C) influence on many(D) popular
vocal and instrumental music.

C

Questions 1-11

Before the 1500's, the western plains of North America were dominated by farmers. One group, the Mandans, lived in the upper Missouri River country, primarily in present-day North Dakota. They had large villages of houses built close together. The tight arrangement enabled the Mandans to protect themselves more easily from the attacks of others who might seek to obtain some of the food these highly capable farmers stored from one year to the next.

The women had primary responsibility for the fields. They had to exercise considerable skill to produce the desired results, for their northern location meant fleeting growing seasons. Winter often lingered; autumn could be ushered in by severe frost. For good measure, during the spring and summer, drought, heat, hail, grasshoppers, and other frustrations might await the wary grower.

Under such conditions, Mandan women had to grow maize capable of weathering adversity. They began as early as it appeared feasible to do so in the spring. clearing the land, using fire to clear stubble from the fields and then planting. From this point until the first green corn could be harvested, the crop required labor and vigilance.

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