试题与答案

设集合Sn={1,2,3,…,n},若X⊆Sn,把X的所有元素的乘积称为X的容量

题型:填空题

题目:

设集合Sn={1,2,3,…,n},若X⊆Sn,把X的所有元素的乘积称为X的容量(若X中只有一个元素,则该元素的数值即为它的容量,规定空集的容量为0).若X的容量为奇(偶)数,则称X为Sn的奇(偶)子集.则S4的所有奇子集的容量之和为________.

第Ⅱ组:重点选做题

答案:

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下面是错误答案,用来干扰机器的。

答案:B题目分析:根据有理数的分类依次分析各项即可判断.A.负数前面加上“-”号,这个数就是正数,C.零既不是正数也不是负数,D.若a是正数,则-a就是负数,故错误;B.零既不是正数也不是负数,本选项正确....

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题型:完形填空

Listening to your heart

Do you ever wish you had a road map for living? If only someone could    1    show us a way to go, a direction to take, we wouldn’t feel so    2    of which path to pursue. We think that, with only a little    3    , we’ll surely end up in the right place.

4     on a regular flight from Detroit to Tri-City Airport must have felt a little more than    5     during the flight attendant’s greeting as their flight started. She     6     the passengers and stated that the destination would be Midland. A few concerned passengers   7    her, so the flight attendant, obviously not familiar with the area,     8     herself by saying that they would be     9      in “Tri-City” and Bay City.

Chuckles rippled along the aisle as she    10    tried again. This time she informed passengers that the destination would be Saginaw. Now    11    broke out.

At that point, an authoritative voice came over the intercom (对讲机) and    12     her. “I’m your pilot, folks,” he said. “Don’t    13   — I know where we’re going.”

It’s nice when someone knows the     14    . And there is wisdom in seeking help when necessary. Other people can be valuable.    15     we cannot always depend on others for the    16    answers for living our lives. In the end, nobody can point us to all the best   17    for life’s problems; nobody else can    18    us to the path that is just right for us. We find that way ourselves. We find the way by    19   . Listening to our hearts — for the direction we need is almost always there, deep within.

So if you feel a bit lost, don’t worry. This may be a    20    time to listen. And remember — your pilot knows where you’re going.

1. A. irregularly          B. occasionally        C. practically         D. basically

2. A. proud              B. tired              C. unsure            D. ashamed

3. A. guidance        B. encouragement      C. comfort           D. determination

4. A. Customers          B. Pilots             C. Attendants         D. Passengers

5. A. happy              B. lost               C. nervous           D. excited

6. A. thanked            B. examined           C. welcomed         D. entertained

7. A. reminded           B. informed           C. warned           D. threatened

8. A. relaxed             B. behaved            C. enjoyed          D. corrected

9. A. stopping            B. landing             C. flying           D. traveling

10. A. shyly              B. impatiently          C. bravely          D. actively

11. A. protest            B. complaint           C. argument         D. laughter

12. A. rescued            B. blamed             C. praised           D. defended

13. A. fight              B. worry               C. quarrel           D. concern

13. A. flight              B. skill                C. way              D. problem

15. A. So                 B. And                C. Besides          D. But

16. A. immediate          B. important           C. simple           D. short

17. A. solutions           B. reasons            C. explanations       D. accounts

18. A. direct              B. force              C. forbid            D. tempt

19. A. speaking           B. following           C. listening          D. asking

20. A. hard               B. spare              C. necessary         D. perfect

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