题干

水稻是喜温植物,春季育秧时,农民通常在傍晚向秧田灌水,早晨再将水放出,以防霜冻,这是因为水的____较大,当气温降低时,水能放出较多的热量,如果某秧田中水的温度降低了2℃,放出了3.36×107J的热量,则该秧田内的水的质量为____ kg.[已知c=4.2×103J/(kg•℃)].
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比热容,4000

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Weather influences health, intelligence and feelings. ____

In August, it is very hot and wet in the southern part of the United States. ____ In the Northeast and the Middle West, it is very hot at some times and very cold at other times. People in these states have more heart trouble after the weather changes in February or March.

____ For example, in a recent report by scientists, IQ of a group of students was high when a very strong wind came, but after the strong wind, their IQ was 10% lower. The wind can help people have more intelligence. Very hot weather, on the other hand, can make it lower. Students in many schools of the United States often get worse on exams in the hot months of the year.

Weather also has a strong influence on people’s feelings. Winter may be a bad time for thin people. They usually feel cold during these months. They might feel unhappy during cold weather. ____ Generally speaking, at about 18℃, people become stronger and better.

Low air temperature may make people forgetful. People leave more bags on buses and in shops in cold days.

____ sometimes, it may be the weather’s problem.

A, The weather can also influence intelligence.

B, So, different weather makes people feel different.

C, But fat people may have a hard time in hot summer.

D, Are you feeling sad, tired, forgetful, or unhappy today?

E,Warm weather can have a bad effect on health.

F, People there have heart trouble and other kinds of health problems during this month.

G,people may have more intelligence when low air pressure comes.