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问题 选择题

绿色植物进行光合作用的原料是（　　）

①二氧化碳    ②氧气    ③水  ④淀粉（有机物）

A．①②

B．③④

C．①③

D．②④

答案

绿色植物通过叶绿体，利用光能，把二氧化碳和水转化成储存能量的有机物，并且释放出氧气的过程，叫做光合作用，如图所示：即光合作用的原料是二氧化碳和水，产物是有机物和氧气，条件是光，场所是叶绿体．

故选：C

选择题

读图，下列几组数字有可能为A地多年平均降水量的是：（  ）

A．200mm

B．400mm

C．680mm

D．890mm
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单项选择题

One of the most convenient and cheapest ways to see America is by riding a Greyhound bus. This interstate bus system connects all major cities in the United States, (52) people with frequent and convenient service. The bus system even has an international service (53) makes connection with cities in Canada and Mexico.

Its network even extends to some of the smaller towns and out-of-the-way communities (54) the great interior of the country. Traveling by bus may (55) longer than flying by plane, but the terminals are located in the center of most cities and there is (56) to the downtown area. These buses are comfortable and air-conditioned. They are all equipped with toilets in the rear to (57) the convenience of the passengers, but there are some very severe (58) of conduct which are strictly enforced. On all buses (59) is forbidden and the consumption of alcoholic drinks is not allowed.

(60) bus travel may not be suited to everyone’s taste, it affords budget travelers the (61) to see America in comfort and safety and at a leisurely unhurried pace.

52().

A.giving 

B.providing 

C.offering 

D.favoring
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