56 A) To get their share of clean air.

57 C) Offering preferential treatment to wealthy countries.

58 B) Our relationship to the plant world.

59 D) By pooling their efforts together.

60 C) Share life with nature.

Passage Two

61 B) Attend the school once they are admitted.

62 A) To make sure they get qualified students.

63 C) It allows them little time to make informed decisions.

64 D) It places students from lower-income families at a disadvantage.

65 B) Avoid choosing early decision unless they are fully prepared.

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