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问题 选择题

如图，树枝上的一只松鼠看到一个猎人正在用枪水平对准它，在子弹出枪口的瞬间，松鼠开始运动，下述各种运动方式中，松鼠能逃脱厄运不被击中的是(树枝足够高)  ①自由落下   ②竖直上跳   ③迎着枪口，沿AB方向水平跳离树枝

④背着枪口，沿AC方向水平跳离树枝

A．①

B．②

C．③

D．④

答案

答案：B

平抛运动的竖直分运动为自由落体，如果松鼠也做自由落体，肯定被水枪击中，①错；如果松鼠迎着枪口，沿AB方向水平跳离树枝，竖直方向运动情况和水完全一样，肯定被击中，③错；同理④错；

改错题

下面短文中有10处语言错误。请在有错误的地方增加、删除或修改某个单词。

增加：在缺词处加一个漏字符号（∧），并在该漏字符号下写上该加的词。

删除：把多余的词用斜线（ \ ）划掉。

修改：在错的词下划一横线，并在该横线下写上修改后的词。

注意：1、每处错误及其修改均仅限一词；

2、只允许修改10处，多者（从第11处起）不计分。

Last Saturday, mom and I went to buy a down jacket for my grandpa. When we got to a big store, we saw down jackets of vary colours and styles. There were so many of them that it spent us quite a while to decide which one to buy. Finally, under the help of the shop assistant, he selected a black thick jacket for grandpa. Immediately, we returned back home to show itto my grandpa. Seeing it, he was very happy and couldn’t wait to put on. But we were annoyingto find something was wrong with the zipper. Hurriedly, I took it back to the store and explained the shop assistant the problem To my satisfaction, she is very kind and helped me choose another one patiently. Stand in front of the mirror, my grandpa looked at himself in the new coat, smilingcontently. How delighted I was! 
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单项选择题

应激时蛋白质代谢变化中不正确的是（）

A.糖皮质激素↑引起蛋白质分解加强

B.胰岛素↓引起分解↑合成↓

C.生长激素↑引起分解↑

D.骨骼肌蛋白质分解↑

E.肝脏合成急性期蛋白↑
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