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问题 填空题
一个长方形的长与宽分别为16
3
cm和16cm，绕它的对称中心旋转一周所扫过的面积是______cm2；旋转90度时，扫过的面积是______cm2．
答案

AC=16

3
÷2=8
3
cm，OC=16÷2=8cm，

OA=

(8
3
)2+82
=16cm，

绕它的对称中心旋转一周所扫过的面积是：162π=256πcm2；

可知

BAC′
的圆心角为：90°+30°×2=150°，A′E=（8
3
-8）cm，旋转90度时，扫过的面积是：256π-[
30π×162
360
×162π-
1
2
×8×16]×2-（8
3
-8）2=（
640
3
π+128
3
-128）cm2．

故答案为：256π；（

640
3
π+128
3
-128）．

填空题

根据首字母或汉语提示写单词。

1. Winter lasts from December to F_______ in China.

2. My father went on h_______ last month. He had a good time.

3. Turn down the TV, please. The baby is a_______.

4. Everyone h_______ they will come to Beijing in 2010.

5. After the two astronauts walked out of the spacecraft, they w_______ their hands to us.

6. I'm tired now. I ________ (花费) an hour cleaning the classroom by myself.

7. Her father gave a ________ (金色的) watch to her as a birthday present.

8. Shakespeare was a ________ (成功的) poet.

9. There are 20 _______ (乘客) on the bus.

10. Boeing 747 travels the ________ (最远) of all the planes, from London to Beijing.

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配伍题 B型题

不溶性固体分散体载体材料
水溶性固体分散体载体材料
包合材料
肠溶性载体材料

A、PEG类

B、丙烯酸树脂RL型

C、β环糊精

D、淀粉

E、HPMCP
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