选择题：“天问一号”在经历了7个月的“奔火”之旅和3个月的“环火”探测，完成了长达5亿千米的行程，登陆器“祝融”号火星车于2021年5月15日7时18分从火星发来“短信

题目分类：中考
题目类型：选择题
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题目内容：

“天问一号”在经历了7个月的“奔火”之旅和3个月的“环火”探测，完成了长达5亿千米的行程，登陆器“祝融”号火星车于2021年5月15日7时18分从火星发来“短信”，标志着我国首次火星登陆任务圆满成功，请将5亿这个数用科学记数法表示为（）

A.

B.

C.

D.

参考答案：

答案解析：

You can only borrow two books ____________ if you don’t have a library card.

You can only borrow two books ____________ if you don’t have a library card.

分类：中考题型：选择题

Kelly White loves all sports, __________skating.

Kelly White loves all sports, __________skating.

分类：中考题型：选择题

Susans mother looks soyoung. Its hard to imagine shes already in her ______.

Susans mother looks soyoung. Its hard to imagine shes already in her ______.

分类：中考题型：选择题

—Dear, how is yourhomework going? —Oh, mom, Ive justfinished ________ of it.

—Dear, how is yourhomework going? —Oh, mom, Ive justfinished ________ of it.

分类：中考题型：选择题

In our school everystudent has to choose a club to join, so about one ________ s

In our school everystudent has to choose a club to join, so about one ________ students havejoined t

分类：中考题型：选择题