corn/soybean and pesticide GWD原题

ruirui_hsu

一看这个题就是做过
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108、【农药】有种农药还不知化肥对corn很有益，但对soyer bean 有害，哪怕很微量也有害，尽管corn 和 soyer 不可能同时种在一块地里，但是大多数农民都不用这种农药还不知化肥，问为什么。我选了为了保持土壤肥力，一般两种作物是隔年轮种的        by770



17. GWD31-Q17

It is crucially important to farmers that the herbicides they use to control weeds not damage their crops. One very effective herbicide is safe for corn, but soybeans are damaged even by the herbicide’s residue, which remains in the soil more than a year after the herbicide is applied. Soybeans and corn are not sown together in the same filed; nevertheless, most farmers are reluctant to use the herbicide on their corn.

Which of the following, if true, provides the strongest justification for the farmers’ reluctance?



A.The residue of the herbicide in the soil a year after application is not enough to control most weeds effectively.

B.To maintain the nutrients in the soil, corn and soybeans are often planted in a field in alternate years. (1’58”) (The residue will last for more than a year after appliance, so the soybeans will be affected if corns and soybeans are planted in alternate years.)

C.The demand for soybeans is growing faster than is the demand for corn.

D.For maximum yield, soybean plants are grown closer together to each other than are corn plants.

E.The application of herbicides is less critical for soybean than for corn crops.