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问题 选择题

金属钒被誉为“合金中的维生素”．其中钒（V）的化合价为+5价的氧化物的化学式为（　　）

A．VO

B．VO2

C．V2O3

D．V2O5

答案

钒（V）的化合价为+5价，氧元素显-2价，其化学式为：V2O5．

故选D．

改错题

单句改错

小题1:He is as clever boy as his brother.

小题2:I consider this impossible to finish this task on time.

小题3:He like swimming in particularly in summer

小题4:I could hardly find suitable words expressing myself.

小题5:You should suit yourself to the new environment.

小题6:We were out of breathe when we reached the top of hill.

小题7:You should keep your words after you promise to help.

小题8:I’d like to go to the party last night but I had to finish a report.

小题9:I hate being made fun.

小题10:John would rather stay at home than going out.
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单项选择题

12月22日，测者纬度等于20°S，向（）测得太阳中天高度等于（）。

A．南；86°.5

B．北；86°.5

C．北；46°.5

D．南；46°.5
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