如图所示是四冲程汽油机的一个工作循环示意图,其中属于利用机械能转化内能冲程的是(

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问题:

如图所示是四冲程汽油机的一个工作循环示意图,其中属于利用机械能转化内能冲程的是(  )

A.B.C.D.

考点:热机的定义
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阅读理解

     It was a Sunday and the heavy storm had lasted all night.The morning after the storm,though,was

beautiful:blue skies,warm air and a calm,inviting sea touching the shore gently.

     My father realised it was a good day for fishing and invited my sister and me to go with him.I was

only 14 and fishing had never been my thing,but I decided to go all the same.I'm_so_glad_I_did.

     On the road to the harbour we could see the terrible destruction on the coast,but the harbour itself

was in fairly good shape.After all,it was protected by the arms of a bay that had only one tiny channel

to the sea.As we got on board,we noticed two big humps(脊背) in the distance.

     On approaching them,we saw it was a mother whale with her baby.We couldn't believe it-there aren't

any whales along the coast here.The storm must have driven them across the ocean into the bay,in which

the still water was so badly polluted that nothing could survive.

     The little baby whale-actually as big as our boat-was obviously stuck and could not move.The mother

dived under the water and came up suddenly,making big whirlpools(漩涡) and waves."She's trying to

help her baby,but on the wrong side,"my father said.At this point,my father moved our boat in a semicircle to the other side and,heading the boat towards the baby whale,pushed it gently.With our several gentle

pushes the big hump turned over and disappeared under water.Then it swam up right beside its mum.

They struggled in their desperate attempts to escape but missed the exit and started heading in the wrong

direction.We hurried up to the whales and tried to lead them towards the bay channel.Slowly,they let us

lead them,sometimes rising from the water right beside us to breathe-and to give us a trusting look with

those huge eyes.Once they hit their first part of clean water flowing straight from the sea,the mum gave

us a wave with her tail and off they swam into the distance.

     In the excitement it had felt like only a few minutes,but we had been with those wonderful animals for

almost an hour and a half.That was the simple and lasting beauty of the day.Nearly four decades later,I

still look back fondly to that golden day at sea.

1. The author says "I'm so glad I did."(in Para. 2)because_____  .

A. he witnessed the whole process of fishing

B. he enjoyed the beauty of the calm sea

C. he experienced the rescue of the whales

D. he spent the weekend with his family

2. The harbour survived the storm owing to ________.

A. the shape of the harbour

B. the arms of the bay

C. the still water in the channel

D. the long coast line

3. The mother whale failed to help her baby because ________.

A. she had stayed in the polluted water for too long

B. the whirlpools she had made were not big enough

C. she had no other whales around to turn to for help

D. the waves pushed her baby in the wrong direction

4. What is the theme of the story?

A. Saving lives brings people a sense of happiness.

B. Fishing provides excitement for children.

C. It's necessary to live in harmony with animals.

D. It's vital to protect the environment.  

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论述CIO的理想知识结构和能力结构。

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出生时存在,4~7个月左右消失的反射是()

A.握持反射

B.平衡反射

C.吸吮反射

D.吞咽反射

E.提睾反射

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解释下面词的中文意思:

LOF,LOS,WDM,EDFA.OTUM

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某公司目前有普通股200万股(每股面值1元,市价4元),资本公积280万元,未分配利润1260万元。发放8%的股票股利后,公司的未分配利润将减少64万元,股本增加16万元。()

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