5. The best title of the passage is _______.

A. Escaping from the Windows　　　 B. Save Yourself in the Burning House

C. Knowledge on Fire　　　　　　　　　 D. Waiting for Help

[答案及解析]

4. Open the window so that _______ if the building is on fire.

A. you can get fresh air 　　　　　　 　B. you can call for help

C. you can easily jump off 　　　　　 　D. you can be seen first

3. Which of the following escaping way is NOT right? _______.

A. You can escape though stairways.　　　　　 　B. You can choose fire escapes.

C. Escape from the windows that open onto a roof.　 D. Use a lift to come down at once.

2. It is possible to escape through the windows _______.

A. if there are some bushes on the ground　 B. if you are strong enough

C. if you live on a lower floor　　　 D. If you have a long rope

1. It is important to _______.

A. put out the fire in the burning house B. know the ways to escape the fire

C. jump off a burning house 　　　　 D. keep the door closed

24．(本小题满分10分)

已知等差数列中，.

⑴求数列的通项公式；^K*s5u

⑵若数列满足，设，且，求的值.

嘉兴市第一中学2009学年第二学期月考考试

23．(本小题满分9分)

已知等比数列的前项和为，且。

⑴求、的值及等比数列的通项公式；

⑵设，求数列的前项和。

22．(本小题满分9分)

已知为数列的前项和，_。

(1)求的通项公式；^K*s5u

　 (2)求_。

21. (本小题满分8分)

已知个数成等差数列，它们的和为，平方和为，求这个数。

20．(本小题满分6分)

已知是等差数列，其中

(1)求的通项；

(2)数列从哪一项开始小于0；

(3)求值。