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问题 选择题

下图表示2000-2010年我国某省耕地面积和粮食产量变化以及2004年、2010年农作物播种面积结构。读图回答下列问題。

小题1:2000-2010年，该省粮食产量总体呈上升态势的主要原因是

①耕地面积增加 ②风调雨顺 ③农业劳动力增加 ④优良品种的培育 ⑤政策扶持

A．④⑤

B．②④

C．②④⑤

D．③④⑤小题2:与2004年相比，2010年蔬菜瓜类播种面积变化较大，其最主要的原因是

A．水利基础设施的完善

B．市场需求的扩大

C．土壤肥力的提高

D．机械化的普及

答案

小题1:A  

小题2:B

题目分析：此题不难，解题关键是结合图中信息和所学农业的区位条件。

小题1:根据图中信息，2000-2010年，该省耕地面积减少，我国的自然灾害频繁，从事农业的劳动力没有增加，该省粮食产量总体呈上升态势的主要原因是优良品种的培育和政策扶持。

小题2:与2004年相比，2010年蔬菜瓜类播种面积变化较大，这主要是由于市场对蔬菜瓜果的需求扩大。

单项选择题

“小型船舶推荐航路”指为小型船舶（队）推荐的（）.

A、下行航路

B、上行航路

C、横驶区

D、上下行航路
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单项选择题

When a disease of epidemic proportions threatens the public, scientists immediately get to work, trying to locate the source of affliction and find ways to combat. Vaccination is one of the effective ways to protect the (1) population of a region or country which may be (2) grave risk. The process of vaccination allows the patient’s body to (3) immunity to the virus or disease so that, if it is encountered, one can fight it (4) naturally. To accomplish this, a small weak or dead (5) of the disease is actually injected into the patient in a controlled environment, (6) his body’s immune system can learn to fight the invader (7) . Information (8) how to penetrate the disease’s defenses is (9) to all elements of the patient’s immune system in a process that occurs naturally, in which genetic information is passed from cell to cell. This makes sure that (10) the patient later come into contact with the real problem, his body is well equipped and trained to (11) with it, having already done so before.

There are, however, dangers (12) in the process. (13) , even the weakened version of the disease contained in the vaccine proves (14) much for the body to handle, resulting in the immune system (15) , and, therefore, the patient’s death. Such is the case of the smallpox vaccine, (16) to eradicate the smallpox epidemic that nearly (17) the whole Native American population and killed massive numbers of settlers. (18) 1 in 10,000 people who receive the vaccine (19) the smallpox disease from the vaccine itself and dies from it. Consequently, the process, which is truly a (20) , may indeed hide some hidden curses.

17（）

A.wiped out

B.ruled out

C.break down

D.died out
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