24 According to the passage, acidic soils tent to be associated with
(A) a high salt content
(B) an increase in farming
(C) large amounts of rain
(D) glacial meltwater

20.Which of the following statements is best supported by paragraph 4? (A)Agricultural development contributed to development in other parts of the economy. (B)European agricultural products were of a higher quality than those produced in the United States. (C)The growing settlement of the West led to a decrease in agricultural production. (D)Farmers were influenced more by government policies than by market opportunities.

21 What aspect of North America does the passage mainly discuss? (A) The wide variety of climates (B) Soil types and vegetation patterns (C) Improved irrigation methods and the expansion of agriculture (D) The change in precipitation patterns

22 The word “spawn ” in line 1 is closest in meaning to (A) distinguish (B) eliminate (C) protect (D) create

23 The word “partitioning” in line 2 is closest in meaning to (A) division (B) modification (C) opening (D) circulating

25 The word “enhanced” in line 13 is closest in meaning to (A) implied (B) increased (C) indicated (D) informed

26 How did glacial meltdown affect the soil in North America? (A) It redistributed the soil types (B) It added salt to the soil (C) It made the soil more neutral in content (D) It added minerals to the soil

27 The phrase “this regionalization scheme” in line 19 refers to the (A) movements of glacial deposits (B) patterns of natural vegetation (C) human modification of the North American environment (D) distinction between humid America and arid America

28 The word “transition” in line 23 is closest in meaning to (A) elevation (B) change (C) advantage (D) condition

29 The passage supports which of the following statements? (A) Arid America is not necessarily characterized by the presence of deserts (B) Most of Canada and the northeastern United States consists of short-grass prairies wherever natural vegetation has not been modified by humans (C) The accumulation of loess is primarily the result of irrigation (D) Glaciation removed the fertile layer of soil from much of the Mississippi Valley

30 What does the passage mainly discuss? (A) The history of the photoflash (B) Theories about how the eye reacts to light (C) The technology of modern photography (D) The dangers of using the early photoflash