小明利用蜡烛进行下列实验,有关说法不正确的是 [ ] A.切一小块蜡烛放入水中,

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问题:

小明利用蜡烛进行下列实验,有关说法不正确的是 [ ]

A.切一小块蜡烛放入水中,蜡烛浮于水面,说明蜡烛的密度小于水

B.在密闭容器中,蜡烛燃烧一段时间后熄灭,说明物质燃烧需要氧气

C.用空气流可吹灭蜡烛的火焰,是因为降低了蜡烛的着火点

D.在密闭容器中,蜡烛燃烧前后,容器的总质量相等,符合质量守恒定律

考点:验证物质燃烧的条件
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指挥员确定总体作战方案的主要依据是()以及气象状况等。

A.现场基本情况

B.灾情发展趋势

C.到场参战力量

D.事故发生单位(部位)建筑布局

E.消防水源以及气象状况

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病原微生物进入机体能否引起疾病取决于()

A.细菌的侵袭力

B.机体的抵抗力

C.细菌的毒力和机体的抵抗力

D.细菌的毒素

E.细菌的毒素与侵袭力

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Running like the wind, roaring like thunder, tigers have long been feared and respected as a king of the animal world.But last week a report said that there are no more than 30 wild tigers left in south China.

This was the conclusion of a team of scientists from China's State Forestry Administration and the World Nature Fund.

The South China tiger, also known as the Chinese tiger, is native to southern China.In the 1950's, there were over 4000 tigers found in mountain forests in the country.But due to the destruction of their natural habitat and uncontrolled hunting, it has been pushed on to the list of the world's top ten most endangered species.

Sixty-six of the big cats can be found in the cages of a dozen zoos around China.But they are nothing like their wild cousins.They have lost their natural skills such as hunting and killing.If they were set free they could not look after themselves.

"Breeding has damaged the quality of the species", said Pei Enle, deputy director of the Shanghai Zoo.

To reintroduce the species into the wild, the country started a programme to send five to ten young tigers to South Africa.Four of them have already arrived.Progress has been made as two elder tigers have recovered some of their instincts(本能)and can hunt wild animals by themselves at the African base.

" South Africans are very experienced in reintroducing big animals to the wild.The country has very good natural conditions for the tigers to learn in", said Lu Jun, office director of the National Wildlife Research and Development Center." We tried in Fujian Province, but it was not successful as there was not a complete eco-chain(生物链) and there was a lack of space."

The tigers should return to China in 2007 when the reservations in Fujian are ready.

1.What is the main reason for the South China tiger becoming one of the world's top ten most endangered species?

A.Because it has lost its natural instincts.        B.Because there is not a complete eco-chain.

C.Because there is no space for it.                 D.Because uncontrolled hunting has destroyed its natural living conditions.

2.How is the programme of sending several tigers to South Africa getting on?

A.Its effect still remains to be seen.

B.Two tigers can already compete with their wild cousins.

C.Some of the tigers are already on the road to recovering their natural skills.

D.The tigers should be able to recover their instincts completely by 2007.

3.By saying " but they are nothing like their wild cousins", the writer means that ______.

A.they are no longer feared by other wild animals

B.they don't know how to hunt or kill

C.a complete change has resulted in the species because of breeding

D.to reintroduce them into the wild has become an urgent task

4.What is the purpose of sending young tigers to South Africa?

A.To help the tigers recover their ability to live in the wild.

B.To provide them with a better environment.

C.To get the tigers to go on a tour.

D.To find a complete eco-chain for them.

5.Which one is not the reason for South Africa being chosen as the training place?

A.Because the tigers can hunt wild animals by themselves at the African base.

B.Because South Africans are skilled at dealing with the tigers.

C.Because there is a complete eco-chain and enough space there.

D.Because the country has good natural conditions for the tigers to learn in. 

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胃痛总的治疗原则是()

A.理气和胃止痛

B.温胃理气止痛

C.疏肝理气止痛

D.通络理气和胃

E.健脾和胃止痛

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人身权利属于( )。

A.权力

B.特殊权利

C.绝对权

D.相对权

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