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据报道：2004年“世界十大科技进展”之一：“美国超音速飞机创飞行时速超万公里的新记录”，该飞机的飞行速度约为______m/s，该速度约为声速的______倍．（V声=340m/s，计算结果取整数）

答案

s=1万公里=1×104km，t=1h，

该飞机的飞行速度：

v=

s
t
=
1×104km
1h
=1×104km/h≈2778m/s；

飞机速度是声速的倍数：

n=

v
v声
=
2778m/s
340m/s
≈8．

故答案为：2778，8．

填空题

根据短文内容，从下面方框中选择适当的词组填空。   

One afternoon just before Christmas, an old kind man was walking in the street when he saw a little boy crying   小题1: a beautiful shop window. The old man asked why he was crying there. The little boy said that he lost the ten dollars given by his mother. When the old man heard this, he   小题2: a small wallet and gave him what was inside. The little boy thanked him and stopped crying and smiled. The man  小题3: .

An hour later, the old man was returning home by the route. To his surprise, he saw the boy at the same place. He went up to him and asked if he had lost his money again. The little boy said that he had found the lost ten dollars. He   小题4: him there. He wanted to  小题5:  the ten dollars to him.
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问答题 简答题

简述5%～10%葡萄糖溶液的作用。
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