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问题 选择题
若x＞0，y＞0且
2
x
+
8
y
=1，则xy有（　　）
A．最大值64B．最小值
1
64
C．最小值
1
2
D．最小值64
答案

因为x＞0，y＞0

所以

2
x
+
8
y
=1≥2
2
x
?
8
y
=8
1
xy

?xy≥64当且仅当x=4，y=16时取等号，

故选D

填空题

根据句意和单词首字母提示写出单词

1. Holland is a E_______ country.

2. He likes singing, e________ singing p_________ songs.

3. Our new English teacher can play many m________ instruments.

4. Maybe when I g_________ I'll be a flight a ________.

5. She has never been to an a__________ park. N _________ have I.

6. There is an old f_________ car in the museum.

7. I d________ that secret yesterday.

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单项选择题

面漆涂刷应在设备、管道及支架涂刷的防锈漆干透后进行；并且（）无脱落、结疤、漆流痕方可进行，如有上述缺陷，应处理后再进行面漆游

A.漆膜光滑

B.无返锈

C.无划痕

D.颜色均匀
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