试题与答案

木炭在一定条件下燃烧既有CO2生成,也有CO生成.若要证明两种气体都要存在,应先

题型:填空题

题目:

木炭在一定条件下燃烧既有CO2生成,也有CO生成.若要证明两种气体都要存在,应先将气体通过澄清的石灰水,澄清的石灰水变浑浊,证明有CO2存在.写出CO2与澄清的石灰水反应的化学方程式______.然后将气体干燥后通过灼热的氧化铜,观察到______,证明有CO存在.实验后向燃着的木炭上洒水使其熄灭,其灭火的原理是______.

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

阅读理解。

     A Scotsman and an Englishman lived next door to each other. The Scotsman owned a hen

and each morning he would look in his garden and pick up his hen’s egg for breakfast. One

morning he looked into his garden and saw that the hen had laid an egg in the Englishman’s garden.

     He was about to go next door when he saw the English-man pick up the egg. The Scotsman

ran up to the English-man and told him that the egg belonged to him because he owned the hen.

The Englishman disagreed because the egg was on his property(财产).

     They argued for a while until finally the Scotsman said, "In my family we normally settle disputes

by the following actions: We kick each other and we compare the time how long it takes us to

get back up. Whoever gets up quicker wins the egg."

     The Englishman agreed to this, so the Scotsman found his heaviest pair of boots and put

them on. He took a few steps back, then ran toward the Englishman and kicked as hard as he

could in his stomach.

     The Englishman fell to the floor, holding his stomach and howling in pain for 10 minutes.

Eventually the English-man stood up and said, "Now it’s my turn to kick you." At this time,

the Scotsman said, "Aye Lad, maybe you should just keep the egg."

1. What do we know about the hen?_____

A. It belonged to the two men equally.

B. It laid an egg every other day.

C. Its eggs were usually cooked by the Scotsman as breakfast. 

D. It usually laid eggs in the Englishman’s garden.

2. The underlined word "disputes" in Paragraph 3 means "_______".

A. arguments    

B. wars    

C. plans      

D. Debts

3. What’s the real purpose of the Scotsman’s proposal (提议)?_____

A. He wanted to get his egg back from the Englishman.

B. He wanted to solve their dispute.

C. He wanted to teach the Englishman a lesson.

D. He wanted to find out who was the stronger of them.

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题型:问答题

[问题4] 若系统增加新的预约需求,其业务处理描述如下: 若图书流通室没有读者要借的书,则可为该读者建立预约登记,需要记录读者ID、书的ISBN号、预约时间和预约期限(最长为10天)。一旦其他读者归还这种书,系统将自动查询预约登记表,若存在有读者预约该书的记录,则将该图书的状态修改为“已预约”,并将该图书ID写入相应的预约记录中(系统在清除超出预约期限的记录时解除该图书的“已预约”状态),同时通过E-mail通知该预约读者办理借阅手续。对于超出预约期限的预约记录,系统将自动清除。 为满足上述需要,应对上图所示的实体联系图如何修改或补充,请给出修改后的实体联系图,并对关系模式做相应的修改或补充,指出新增关系模式的主键和外键。

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