试题与答案

下列CO和CO2的收集方法说法正确的是( ) A.都能用排水法收集 B.都能用向

题型:选择题

题目:

下列CO和CO2的收集方法说法正确的是(  )

A.都能用排水法收集

B.都能用向上排气法收集

C.CO只能用排水法,CO2一般用向上排气法

D.CO只能用向下排气法,CO2一般用向上排气法

答案:

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People who use their left hands are just starting to get better treatment. But why they get all these bad names in the first place? One reason may be that there are not as many left-handed people as there are right-handed people. There is one left-handed person for every five right-handed ones. People who are different are often thought to be wrong. But attitudes do seem to be changing. Fair-minded right-handed people are finally starting to give left-handed people a hand.

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A.He can only use his right hand.

B.He can only use his left hand.

C.He can use either his left hand or his right hand.

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A.Fair-minded right-handed people want to change the habit of the left-handed people

B.Fair-minded right-handed people are starting to help the left-handed people

C.Fair-minded right-handed people are starting to use left hand to write and so on

D.Fair-minded right-handed people are starting to give up using their left hands小题3: After we read the article we can certainly know that _______.

A.left-handed people have been treated poorly

B.the number of the left-handed people is larger than that of right-handed people

C.right-handed people are much cleverer than left-handed people

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A.At one time, left-handed people were forced to use their right hands.

B.Left-handed people today are being treated better than those in the past.

C.There are not as many left-handed people as there are right-handed people today.

D.“Dexterous” comes from Latin, means “evil” and English “sinister” means “handy”.

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(3)若铁环与箱底每次碰撞都没有能量损失,求小环从开始运动到最终停止在箱底,所走过的总路程是多少?

       

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