如果采煤机内喷雾装置不能正常喷雾，外喷雾压力不得小于（）MPa。A、2B、3C、4D

If you get lost, this is what you should do. Sit down and stay where you are. Don’t try to find your friends—let them find you. You can help them find you by staying in one place. There is another way to help your friends or other people to find you. You can shout or whistle （吹口哨）three times. Stop. Then shout or whistle three times again. Any signal（信号）for three times is a call for help.

Keep up shouting or whistling. Always three times together. When people hear you, they will know that you are not just making a noise for fun. They will let you know that they have heard your signal. They will give you two shouts or two whistles. When a signal is given twice, it is an answer to a call for help.

If you don’t think that you will get help before night comes, try to make a little house with branches（树枝. Make yourself a bed with leaves and grass.

When you need some water, you have to leave your little branch house to look for it. Don’t just walk away. Pick off small branches and drop them as you walk in order to go back again easily. When you are lost, the most important thing to do is to stay in one place.

小题1:If you get lost in the forest, you should___________.            

A．try to find your friends

B．stay in one place and give signals

C．walk around the forest

D．shout as loudly as possible小题2:Which signal is a call for help?    

A shouting here and there         B. shouting or whistling three times together

C. crying twice                   D. whistling every where in the forest

小题3:When you hear two shouts or two whistles, you know that_____.

A．someone is afraid of an animal

B．people will come to help you

C．someone needs help

D．something terrible will happen小题4:What’s the meaning of the underlined sentence?(划线句子)

A．Drop branches to find your way back

B．Pick off branches to build another house

C．Use branches to make a bed

D．Drop branches to look for water小题5:The main（主要的）idea of the passage is_____________.

A．how to travel in the forest

B．how to spend the night in the forest

C．what you should do if you want to get some water

D．what you should do if you are lost in the forest

在SMNPv1管理框架中，如果代理需要向管理站报告一个异常事件，则代理就发出trap报文，以下事件中不属于异常事件的是( )。

A．通信链路失效

B．系统重新启动

C．报文认证失败

D．检索的变量不存在

Excel 97的工作簿、工作表、单元格的关系是( )。

A．工作簿由工作表构成，工作表由单元格构成

B．工作表由工作簿构成，工作表由单元格构成

C．工作簿由工作表构成，工作簿由单元格构成

D．工作表由单元格构成，工作簿是工作表的一部分

D

As they migrate（迁移），butterflies and moths choose the winds they want to fly with，and they change their body positions if they start floating in the wrong direction．This new finding suggests that insects may employ some of the same methods that birds use for traveling long distances．Scientists have long thought that insects were simply at the mercy of the wind．

Fascinating as their skills of flight are，migrating behavior has been difficult to study in insects because many long distant trips happthousands of feet above ground．Only recently have scientists developed technologies that can detect such little creatures at such great heights．

To their surprise，though，the insects weren’t passive travelers on the winds．In autumn，for example，most light winds blew from the east，but the insects somehow sought out ones that carried them south and they positioned themselves to navigate directly to their wintering homes．

Even in the spring，when most winds flowed northward，the insects didn’t always go with the flow．If breezes weren’t blowing in the exact direction they wanted to go，the insects changed their body positions to compensate．Many migrating birds do the same thing．

The study also found，butterflies and moths actively flew within the air streams that pushed them along．By adding flight speeds to wind speeds，the scientists calculated that butterflies and moths can travel as fast as 100 kilometers an hour．The findings may have real-world applications．With climate warming，migrating insects are growing in number．Knowing how and when these pests move could help when farmers decide when to spray their crops．

71．What’s the main idea of the text?

A．Insects migrate with the seasons．     B．Wind helps insects greatly in migrating．

C．Windsurfing insects have real direction．D．Scientists have trouble in observing insects．

72．Scientists originally thought that____________．

A．insects always waited for their favourable winds

B．insects chose the winds they wanted to ride

C．insects were just blown about by the wind

D．insects positioned themselves in the winds

73．It is not easy to stuay the migrating behavior of the insects because____________

A．the little creatures can fly very fast     B．they have no regular migrating courses

C．the wind’s direction is hard to foresee    D．their flight is long and high above ground

74．We can learn from the text that______________.

A．insects fly in the way birds do

B．insects travel more easily in autumn

C．insects never position themselves when flying low

D．insects rest a lot when the wind pushes them along

75．According to the passage，the findings can              ．

A．increase insects in number         B．instruct farmers when to spray

C．prevent climate warming       D．help protect insects

调节阀分单座式和双座式调节阀，由（）、阀座、（）、阀盖等部分组成。