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问题 单项选择题

科技部发布的《全民节能减排手册》数据显示，每人每年少买一件不必要的衣服，能够减排二氧化碳6.4千克；少用一个塑料袋，能够减排二氧化碳0.1克；5层以下，以爬楼梯代替坐电梯，每次平均可减排二氧化碳600克；选择应季蔬菜水果，每千克减排二氧化碳400克；夏季空调调高1℃，每台每天可以减少排放175克二氧化碳。这给我们的启示是（）

A.消费应该量入为出

B.消费不能盲目跟风

C.个人消费可以标新立异

D.绿色消费要从小事做起

答案

参考答案：D

填空题

如果点M（a+b，ab）在第二象限，那么点N（a，b）在第______象限．
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单项选择题

Humans are social animals. They live in groups all over the world. As these groups of people live apart from other groups, over the years and centuries they develop their own habits and ideas, which form different cultures. One important particular side of every culture is how its people deal with time.
Time is not very important in non-industrial societies. The Nuer people of East Africa, for example, do not even have a word TIME that is in agreement with the abstract thing we call time. The daily lives of the people of such non-industrial societies are likely to be patterned around their physical needs and natural events rather than around a time schedule based on the clock. They cook and eat when they are hungry and sleep when the sun goes down. They plant crops during the growing seasons and harvest them when the crops are ripe. They measure time not by a clock or calendar, but by saying that an event takes place before or after some other events. Frequently such a society measures days in terms of "sleeps" or longer periods in terms of "moons". Some cultures, such as the Eskimos of Greenland measure seasons according to the migration of certain animals.
Some cultures which do not have a written language or keep written records have developed interesting ways of "telling time". For example, when several Australian aborigines want to plan an event for a future time, one of them places a stone on a cliff or in a tree. Each day the angle of the sun changes slightly. In a few days, the rays of the sun strike the stone in a certain way. When this happens, the people see that the agreed-upon time has arrived and the event can take place.
In contrast, exactly correct measurement of time is very important in modern, industrialized societies. This is because industrialized societies require the helpful efforts of many people in order to work. For a factory to work efficiently (well, quickly and without waste), for example, all of the workers must work at the same time. Therefore, they must know what time to start work in the morning and what time they may go home in the afternoon. Passengers must know the exact time that an

The Australian aborigines’ way of "telling time" is based on ______.

A. the change of the sun rays
B. the movement of the earth in relation to the sun
C. the position of the stone
D. the position of the tree or the cliff
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