单项选择题
1、 有关碳循环的说法错误的是（　　）
A．量的碳被固结在岩石圈中
B．化石燃料中也有大量的碳
C．碳在岩石圈中主要以碳酸盐形式存在
D．二氧化碳是碳在大气圈中的一形式


2、 与森林生态系统相比，草原生态系统（　　）
A．结构简单
B．组成复杂
C．生物量高
D．以腐屑食物链占优势


3、 下列有关生态效率的说法错误的是（　　）
A．在能量流动过程中，能量的利用效率就叫生态效率
B．生态效率即能量转化效率
C．生态效率是一种比率
D．生态效率就是消费者同化效率


4、
His doctor suggested that he________  his right hand．
A．avoid using
B．avoid to use
C．has avoided using
D．avoids to use


5、回答题
    How can we get rid of garbage? Do we have enough energy sources to meet our future energy　needs?
    These are two important questions that many people are asking today．Some people think that man might be able to solve both problems at the same time．They suggest using garbage as an energy source, and at the time it can save the land to hold garbage．For a long time, people buried garbage or dumped it on empty land．Now, empty land is scarce．But more and more garbage is produced each year．However, garbage can be a good fuel to use．The things in garbage do not look like coal, petroleum, or natural gas; but they are chemically similar to these fossil fuels．As we use up our fossil-fuel supplies, we might be able to use garbage as an energy source．Burning garbage is not a new idea．Some cities in Europe and the United States have been burning garbage for years．The heat that is produced by burning garbage is used to boil water．The steam that is produced is used to make electricity or to heat nearby buildings．In Paris, France, some power plants burn almost 2 million metric tons of the cities garbage each year．The amount of energy produced is about the same as would be produced by burning almost a half million barrels of oil．Our fossil fuel supplies are limited．Burning garbage might be one kind of energy source that we　can use to help meet our energy needs．

What two problems can man solve by burning garbage?
A．The shortage of energy and air pollution．
B．The shortage of energy and the land to hold garbage．
C．Air pollution and the shortage of fossil fuel．
D．Air pollution and the shortage of land to hold garbage．


6、 《楚辞·九歌·国殇》的语言特点是（　　）
A．语言整齐，节奏舒缓
B．语言整齐，节奏短促
C．语言短促，节奏整齐
D．语言舒缓，节奏短促 


7、 甲原是法人乙的业务员，后下海经商。某天，甲在外地办货时，发现法人乙急需的原材料，通知乙的业务经理丙，丙因与甲不和，不同意要，甲索性以乙的名义订了买卖合同，甲的行为属于（　　）。
A．为乙的利益而进行代理
B．原有代理权但现无代理权的无效民事行为
C．侵害乙的名称权的行为
D．效力未定的民事行为


8、 周某到某家具城购买家具，看中了甲公司生产的红木家具一套。双方达成协议，价款8 000元，周某预付订金4 000元，甲公司保证3天内将货送到周某家。双方在挑好的红木家具上作了标记。当晚，家具城失火，该套家具被焚毁。对于本案的处理办法，下列选项中正确的是（　　）。
A．由周某承担损失，周某应补交所欠货款4 000元
B．由甲公司承担损失，甲公司应退还周某预付订金4 000元
C．由周某、甲公司平均分担损失，周某不补交货款，甲公司不退还订金
D．主要由甲公司承担损失，周某也应适当承担损失


简答题
9、(本题满分10分)已知袋中装有8个球，其中5个白球，3个黄球．一次取3个球，以X表示所取的3个球中黄球的个数．
(1)求随机变量X的分布列；
(2)求数学期望E(X)．

10、

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