除用于保护室内钢屋架等建筑构件和设置货架内喷头的闭式系统外，

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问题单项选择题

除用于保护室内钢屋架等建筑构件和设置货架内喷头的闭式系统外，采用闭式系统的民用建筑和工业厂房，其最大净空高度不应大于()m。

A．5

B．6

C．7

D．8

答案

参考答案：D

阅读理解

看图短文填空。

Mid-Autumn Day is one of the _1 traditional festivals in china. It is on _2_ 15th in Chinese calendar.

On that day, families usually get _3_ and have a big meal. In the evening, you know, the moon is big,

bright and _4 . We usually go outdoors to enjoy the 5_ and eat moon cakes in the open air. We have a

good time.

Look! Tom got a lot of presents from his parents. His mother _6_ two lanterns(灯笼) for him. One

was big, the _7_ was small. His father helped him to hang them _8_. When Tom saw the _9_ food on the

table, he was very pleased. After dinner, Tom went out with his parents. They looked at the moon in the

open air. They didn't go home _10_ mid-night. What a happy day!

1. _____ 2. _____ 3. _____ 4. _____ 5. _____

6. _____ 7. _____ 8. _____ 9. _____ 10. _____

单项选择题

井口与河流、沟谷水平距离为1000～2000米的井，表层套管下深应低于河床、沟谷底部不少于（）米。

A.100；

B.300；

C.500；

D.700。