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问题 选择题

–Ten and nine is not ninety. –_____, Miss Zhou.

A. I don’t know        B. I’m fine, too       C. I’m sorry

答案

答案：C

根据前半句可知ten and nine is ninety是错误的，故其对应的答语应是I’m sorry。

解答题
记等差数列{an}的前n项和为Sn．
（1）求证：数列{
Sn
n
}是等差数列；
（2）若a1=1，且对任意正整数n，k（n＞k），都有
Sn+k
+
Sn-k
=2
Sn
成立，求数列{an}的通项公式；
（3）记bn=aan（a＞0），求证：
b1+b2+…+bn
n
≤
b1+bn
2
．
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填空题

hear   stop  remember  take   drive 

Songyang was a bus driver. On March 9, 2013, he 小题1:____________the bus from Liaocheng to Jinan and all the passengers were talking and laughing on the bus. To their surprise, the bus stopped suddenly near the roadside. And they 小题2:___________ a voice coming from the front of the bus, “Quick! Quick! Please call 120, and I feel terrible.” Those were Song’s last words. Then Song lost consciousness. And some passengers helped Song at once. He 小题3:____________ to the hospital as quickly as possible. The bus video told us what happened. At 10:15, Song began to shake his body and he tried his best 小题4:______________the bus and opened the bus door for the passengers. After the doctors checked Song carefully, they said Song was badly ill on the bus but he depended on his strong will to protect all the passengers. Song left us at last because of his serious illness. We小题5:______________ the best driver forever(永远).
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