题目内容
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[主观题]
What is one of the most promising micro operating systems for constrained devices 回答问题,并将答案翻译成中文
提问人：网友xkgo51
发布时间：2022-01-07
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Prehistoric (史前的）had little choice in what he ate. He ate what he could find: roots, eggs, fruits and the meat of smallanimals. Early man had no way to control his food supply. If there was no rain, or the weather was too hot or too cold,plants would not grow, and he would have little or no food. When he ate all the food in one place, he had to move to anotherregion for food.
Man’s life changed when he learned to grow plants and to raise animals. He also learned to use fire to prepare his food. Later, he learned to make tools and weapons, and to make containers to store his food. Man could now live in one place andproduce his own food. So civilization (文明）began. Great civilizations slowly developed in regions where food wasplentiful — along the Nile River in Egypt, and by the Yellow River in China.
The kinds of plants which are raised by man are different in each geographical region. In the colder regions very fewplants can be grown; in the warmer parts of the world great varieties of plants are found. In Asia, rice has become the mostimportant crop. In North America, the most important grains are wheat and com. In Europe and North Africa, wheat is themain crop. In the tropical (热带的）regions of the world，many kinds of fruit grow naturally or arc planted by man.
With the development of methods of keeping food fresh, it became possible to send most food products from one partof the world to another. Today foods are kept fresh in many ways and sent all over the world. Man no longer depends on thefood he grows in his own area only.
As man has learned more about plants and animals, the production of food has become a more technical process. In thefuture, it seems possible that vast quantities of food may come from the ocean. Food may also be produced in new ways.
According to the first paragraph.man has to ensure________
A.the amount of food he needs
B.the quality of the food he needs
C.the quality of his lifeon theearth
D.the number of people livingon the earth
If the weather was extremely bad, early man would？A.raise new crops
B.suffer from hunger
C.raise small animals
D.suffer from diseases
From Paragraph 3 we know that civilizations developed in areas？A.where the weather was good
B.where there was enough rain
C.where there was a large amountof food
D.where there were a great numberof animals
Which of the following is true according to Paragraph 4？A.There are few plants in colder regions.
B.Corn is the most important crop in Asia.
C.There are few plants in hotter regions.
D.Rice is the main crop in Europe.
As man’s knowledge about plants and animals increases,.A.fewer plants will be needed
B.fewer animals will he available
C.more and more land will be
D.more and more food will he available
