单项选择题
1、 设有直线当直线11与l2平行时，等于(    )．
A．1
B．0
C．-1/2
D．-1


2、
A．
B．
C．
D．


3、根据下面内容，回答题：
It takes a long time to grow a tree．How long? Well, pine trees are the quickest growing trees, but still, they take twenty years to reach a size suitable for cutting and harvesting．An oak takes about sixty years to grow to a good size．A redwood may take hundreds of years．Lumber companies, which make their money on trees, depend on those that grow quickly．Therefore, they are always looking for methods to make trees grow faster．So far, the secret to fast growing trees seems to he in " super-seeds．" These are seeds that are gathered from the quickest growing trees in a forest．One company searched 100,000 acres of trees and selected the seeds from just fifteen trees.These two ounces of seed were enough to plant several hundred new trees．Eventually, when these trees have grown, seeds will again be taken only from the fastest growing trees of crop．This process of artificial selection will yield, in the future, a super-tree that will grow in half the time it takes normal trees to develop．Unfortunately, it takes a long time for a plan like this to reach its goal．The Weyerhauser Lumber Corporation, which started its first collection of seed in 1958, is just now beginning to harvest the super-seeds of the first generation of the faster growing trees．

This selection centers on________．
A．the life span of trees
B．the age of redwoods
C．making trees grow quickly
D．cutting trees for lumber


4、 思维的基本过程是（　　）。
A．分析和综合
B．间接性和概括性
C．判断和推理
D．指向性和集中性


5、 合伙人对合伙债务承担（　　）。
A．有限责任
B．按份责任
C．有限连带责任
D．无限连带责任


填空题
6、 过点(1，-l，0)且与直线垂直的平面方程为______.
 


简答题
7、简述艺术与道德的关系。


8、  (1)求曲线Y=ex及直线x=1，x=O,y=0所围成的平面图形(如图3—3所示)
的面积A．
 (2)求(1)中平面图形绕x轴旋转一周所得旋转体的体积Vx.


9、 在教学活动中，如何引导学生掌握科学概念?


10、教师为了更好地了解和教育学生，可以拆看学生的信件。

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