桥式起重机的取物装置主要有（）。 A.吊钩 B.抓斗 C.电磁吸盘_爱下问搜题

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问题多项选择题

桥式起重机的取物装置主要有（）。

A.吊钩

B.抓斗

C.电磁吸盘

D.气动夹具

E.卷筒

答案

参考答案：A, B, C

解答题

设函数f（x）=x²-2|x|-1 （-3≤x≤3），

（1）证明f（x）是偶函数；

（2）画出这个函数的图象；

（3）指出函数f（x）的单调区间，并说明在各个单调区间上f（x）是增函数还是减函数；

（4）求函数的值域．

完形填空

One day, two friends were walking through the desert.__36__ the journey they had a quarrel, and one friend hit __37__ one in the face.
The one who was hit was hurt,__38__ he didn’t say anything. Instead, he wrote in the sand,“Today my best friend hit me in the face.”
They kept on __39__ until they found an oasis(绿洲).They decided to get some water. The one who had been hit fell into the mire(泥潭) and was in danger, but the friend __40__ him.
When he felt all right, he wrote on __41__.“Today my best friend saved my life.”
The one who had hit and saved his best friend asked him,“After I __42__ you, you wrote in the sand and now you write on a stone.__43__”
The other friend replied,“When someone hurts us, we should write it down in sand where winds of forgiveness(宽恕) can blow __44__ away. Bt when someone does something __45__ for us, we must write it in stone where no wind can ever blow it away.”

D．quarreled with

A．interesting