Harvesting proceeded in two stages. In August the Mandans picked a smaller amount of the crop before it had matured fully. This green corn was boiled, dried, and shelled, with some of the maize slated for immediate consumption and the rest stored in animal-skin bags. Later in the fall, the people picked corn. They saved the best of the harvest for seeds or for trade, with the remainder eaten right away or stored for later use in underground reserves. With appropriate banking of the extra food, the Mandans protected themselves against the disaster of crop failure and accompanying hunger.

The women planted another staple, squash, about the first of June, and harvested it near the time of the green corn harvest. After they picked it, they sliced it, dried it, and strung the slices before they stored them. Once again, they saved the seed from the best of the year's crop. The Mandans also grew sunflowers and tobacco; the latter was the particular task of the old men.

1. The Mandans built their houses close together in order to
(A) guard their supplies of food
(B) protect themselves against the weather
(C) allow more room for growing corn
(D) share farming implements

2. The word "enabled" in line 4 is closest in meaning to
(A)covered
(B) reminded
(C)helped
(D)isolated

3.The word "considerable" in line 8 is closest in meaning to
(A) planning
(B) much
(C) physical
(D) flew


4.Why does the author believe that the Mandans were skilled farmers?
(A) They developed effective fertilizers.
(B) They developed new varieties of corn.
(C) They could grow crops in most types of soil.
(D) They could grow crops despite adverse weather.

5. Tile word "consumption" in line 18 is closest in meaning to
(A) decay
(B) planting
(C) eating
(D) conversion

6. Which of the following processes does the author imply was done by both men and women?
(A) Clearing fields
(B) Planting corn
(C) Harvesting corn
(D) harvesting squash.

7. The word "disaster" in line 22 is closest in meaning to
(A)control
(B)catastrophe
(C)avoidance
(D)history

8. According to the passage, the Mandans preserved their food by
(A)smoking
(B)drying
(C)freezing.
(D)salting

9. The word "it" in line 25 refers to
(A)June
(B)corn
(C)time
(D)squash

10. Which of the following crops was cultivated primarily by men
(A) Corn
(B)Squash
(C)Sunflower
(D)Tobacco

11. Throughout the passage, the author implies that the Mandans
(A)planned for the future
(B) valued individuality
(C)were open to strangers
(D)were very adventurous

Questions 12-20

The elements other than hydrogen and helium exist In such small quantities that it is accurate to say that the universe somewhat more than 25 percent helium by weight and somewhat less than 25 percent hydrogen.

Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found In old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic "rays" are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn't seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it; In others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same.

Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to he significantly greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning..

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