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问题 选择题

今年5月18日．英美科学家公布了人类第一号染色体的基因测序图，这个染色体是人类“生命之书”中最长也是最后被破解的一章．据报道，第一号染色体中共有2.23亿个碱基对，2.23亿这个数用科学记数法可表示为　 [ ]

A． 2.23×105

B． 2.23×106

C． 2.23×107

D． 2.23×108

答案

答案：D

听力题

小题1:He said he would________(推荐) me to Professor Wang as his student. 

小题2:I don’t understand why he refused to________(承认) that he had been defeated. 

小题3:Our country is ________(丰富的；充裕的) in natural resources.

小题4:We           (用... 代替)a red ball for the blue one to see if the baby would notice.

小题5:You must not be          (支配) by what other people say.

小题6:Between 1942 and 1945 more immigrants came to California to work in the ship and a____(飞机) industries.

小题7:Most _____________(申请者) know that they have very little chance of getting a visa to California.

小题8:It became ___________(显而易见的) to everyone that they made a wrong decision.

小题9:The m___________ of the first Spanish were religious men who came to teach the Catholic religion to the natives.

小题10:I think you should make an ________(道歉) to her at once.
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选择题

下列离子方程式与所述事实相符且正确的是 [ ]

A. 漂白粉溶液在空气中失效：ClO-+CO2+H2O=HClO+HCO3-

B. AlCl3溶液中加入过量的浓氨水：Al3++4NH3·H2O=AlO2-+4NH4++2H2O

C. 等体积、等浓度的Ba(OH)2稀溶液与NH4HCO3稀溶液混合：

Ba2++2OH-+NH4++HCO3-=BaCO3↓+NH3·H2O+H2O

D. 在强碱溶液中次氯酸钠与Fe(OH)3反应生成Na2FeO4：3ClO-+2Fe(OH)3=2FeO42-+3Cl-+H2O+4H+

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