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问题 问答题

在铁的某氧化物中氧元素的质量分数为30%，则该铁的氧化物的化学式为______．

答案

设铁元素的氧化物的化学式为为FexOy，由题意

16y
56x+16y
×100%=30%，x：y=2：3；故铁的氧化物的化学式为Fe2O3．

故答案为：Fe2O3

完形填空

Ben Lambert thought about      to Greece or Spain, but decided on Canada. I always take

vacations in Europe,” he said. “This time I want to do    I heard that Canada is beautiful，and I know

there are many people there     speak French.” 

Ben is going to Canada’s Great Lakes. He is leaving the first week in June and staying until September. He plans to have a very        vacation. I’m taking walks, going fishing, and going bike riding. I’m planning to spend time in the beautiful countryside. I love nature. I hope I can forget       ! At night, I’m renting videos and sleeping a lot… A great vacation! I can’t wait.

小题1:A. go                  B. going               C. to go

小题2:A. something different    B. different something     C. anything different

小题3:A. who                B. which               C. whom

小题4:A. relax                B. relaxed              C. relaxing

小题5:A. my all problems       B. all my problems       C. my whole problems
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多项选择题

关于学习动机和学习效果，理解正确的是()

A．学习动机影响学习效果

B．两者为一一对应关系

C．要提高学习效果．最终必须依赖学习动机的激发和保持

D．填补知识和技能的空缺．是取得好的学习效果的关键
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