18. Because (A) the diamond is the hardest naturally (B) substance, it is
used in industry for to cut (C), grinding, and boring other hard (D) materials.

19. An electromagnet will remain (A) magnetized only as longer (B) as electricity (C) flows through itD

20. Being (A) chemical compounds, minerals have characteristic (B)shapes and
colors, whereas (C) do rocks not (D).

21. Some of the (A) first aerial photographs (B)were taken from (C) a balloon while (D) the Civil War in the United States.

22. Beyond their (A) importance as a source (B) of food for both (C) people and animals, corn is also used (D) to produce alcohol-based fuels.

23 The Bollingen Prize in (A) poetry established of (B)the Bollingen Foundation, is a $1,000 award (C) for the year's highest (D) achievement in poetry in the United States.

24. For more eighty (A) years, scientists have argued over whether (B) life(C) exists on the planet (D) Mars.

25.Ludmilla Turkevich, known as a translator (A) and scholar in the field (B) of Russian literature, she became (C)a member of the faculty of Princeton University during (D) the Second World War.

26. The Architectural History Foundation was (A) established in 1977 to support (B) the publication (C) of important book (D) on architecture.

27.Wildlife photographers are involved of (A) a new government project to docum (B) the 50 most endangered (C) species in (D) the United States.

28.Most (A) bats roost in crevices, caves, or building(B) by day and are active (C) at night or (D) twilight.

29.Changes within the chemist (A) structure of single genes may (B) be induced by (C) exposure to radiation and extreme (D) temperatures.

30. A landmark famous (A), the Brooklyn Bridge in (B) New Yolk was (C) one of the first woven wire cable suspension bridges ever constructed.(D)

31. Industry's need for (A) more and minerals (B) is a constant challenge (C)to the mining industry to make new discoveries (D).

32. The waters of Hanauma Bay in Oahu, Hawaii, are known (A) for the color(B), diversity and abundant (C) of their (D) tropical fish.

33. The United States government program (A) Head Start prepares children (B) for school encourages (C) the involvement of local communities in the children's Development (D).

34.Brown rice has great (A) nutritional value than white rice because the nutrient-rice outer layers (B) of the rice kernel are (C) not removed from (D) brown rice.

35. After (A) 1845, pestilence spread in Boston, but before then (B) , Boston was a city in which (C) the life span of its citizens was long and disease was rarely (D).

36. Entomologists, scientists (A) who study (B) insects, are often concerned with the fungus, poisonous (C), or virus carried (D) by a particular insect.

37. The eight stripes (A) of red, white, and blue on state (B) flag of Hawaii represent (C) Hawaii's eight major (D) islands.

38. Cool temperatures, shade, moist (A), and the presence of dead (B) organic material provide (C) the ideal living conditions (D) for mushrooms.

39. Metalworkers use the term "machine tool" to refer to (A) a piece of an(B) equipment (C) used for shaping (D) metal.

40. In pools, goldfish are not just (A) ornamental: since (B) they feed on (C) mosquito larva they are also benefit (D) .

C

Questions: 1-10

A seventeenth-century theory of burning proposed that anything that burns must contain material that the theorists called "phlogiston." Burning was explained as the release of phlogiston from the combustible material to the air. Air was thought essential, since it had to provide a home for the released phlogiston. There would be a limit to the phlogiston transfer, since a given volume of air could absorb only so much phlogiston. When the air had become saturated, no additional amounts of phlogiston could leave the combustible substance, and the burning would stop. Burning would also stop when the combustible substance was emptied of all its phlogiston.

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