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问题 填空题
若向量
a
=(1，1，x)，
b
=(1，2，1)，
c
=(1，1，1)，满足条件(
c
-
a
)•(2
b
)=-2，则x=______．
答案

c
-
a
=(0，0，1-x)，

(

c
-
a
)•(2
b
) =(2，4，2)•(0，0，1-x)=2(1-x)=-2，

解得x=2，

故答案为2．

填空题

单词拼写。

1. Much to his mother's surprise, the boy's a         is to become a pilot.

2. Good teaching methods should c         education with pleasure.

3. Do you remember the word the teacher m     last time?

4. Most of the stars in the sky are i     to the naked eyes because they are too far away from us.

5. If you have any trouble, do not h       to come to me, I'd like to help you very much.

6. As we all know, Canada is one of the largest       (移民) countries in the world.

7. You must make an       (道歉) to her for not letting her know it ahead of time.

8. All of the climbers are in a state of       (筋疲力尽) after reaching the top of the mountain.

9. You should be more          (体谅的) towards young people on this issue.

10. Do you know how many Chinese sites there are on the World      (遗产) List?
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单项选择题

环境影响预测的原则所阐述的内容不包括( )。

A．对于已确定的评价项目，都应分析、预测和评估其对环境产生的影响
B．根据其评价工作等级、项目特点和当地要求确定评价的范围、时段、内容及方法
C．预测时应尽量选用通用、成熟、复杂程度高，能满足准确度要求的方法
D．应尽量考虑预测范围内规划建设项目可能产生的环境影响
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