化学与生活密切相关. (1)食品安全日益受到人们关注.下列食品因有毒而不能食用的

题型:填空题

问题:

化学与生活密切相关.

(1)食品安全日益受到人们关注.下列食品因有毒而不能食用的是______,______(填序号).

A.用发酵粉(含碳酸氢钠和有机酸等)制作发面食品  B.霉变的大米、花生

C.用亚硝酸钠(NaNO2)代替食盐烹调的食品        D.食盐腌制的咸鸭蛋

(2)在日常生活中,我们经常要对一些生活物质进行鉴别.鉴别下列各组物质所采用的方法或所加物质完全正确的组是______,______,______.

选项鉴别的物质鉴别方法或所加物质
A蒸馏水和食盐水①导电性  ②蒸发
B食盐和面碱(Na2CO3①稀盐酸  ②闻气味
C假黄金(Cu-Zn合金)和金①看颜色  ②稀盐酸
D厨房内的食醋和酱油①闻气味  ②尝味道
E棉纤维和羊毛纤维①燃烧  ②用氢氧化钠溶液

考点:食品安全天然有机高分子材料金属的化学性质盐的用途物质的鉴别
题型:填空题
已知两定点E(-
2
,0),F(
2
,0)
,动点P满足
PE
PF
=0
,由点P向x轴作垂线PQ,垂足为Q,点M满足
PM
=(
2
-1)
MQ
,点M的轨迹为C.
(I)求曲线C的方程;
(II)若线段AB是曲线C的一条动弦,且|AB|=2,求坐标原点O到动弦AB距离的最大值.
题型:填空题
若抛物线y=ax2+bx+c的顶点在第一象限,与x轴的两个交点分布在原点两侧,则点(a,
c
a
)在(  )
A.第一象限B.第二象限C.第三象限D.第四象限
题型:填空题

在下列委托与代理的关系中,下列说法正确的是:( )

A.有委托必有代理

B.委托是基础关系而代理是单方授权的结果

C.超越代理意味着修改合同

D.代理是委托的外部表现行为

题型:填空题

       Running like the wind, roaring (咆哮) 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 (栖息地) 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.

小题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.小题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.小题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小题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.小题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.

题型:填空题

小儿时期结核病以下哪种最常见()

A.原发型肺结核

B.粟粒性结核

C.结核性脑膜炎

D.结核性胸膜炎

E.支气管内膜结核

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