题目内容：
Aiming to retrieve the Mars rover Opportunity，engineers are imitating Mars surface conditions in a testing laboratory．
参考答案：
答案解析：
单选题：Aiming to retrieve the Mars rover Opportunity，engineers are
- 题目分类：2级
- 题目类型：单选题
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The 20th—century poem suggests to something we have been abl
The 20th—century poem suggests to something we have been able to find nothing ab
Careful testing is necessary before any more experiments can
Careful testing is necessary before any more experiments can continue with the e
George Emest Morrison，an Australian，traveled the “five—foot
George Emest Morrison，an Australian，traveled the “five—foot roads，”or foot paths
外资股发行的招股说明书可以采取（ ）形式。
外资股发行的招股说明书可以采取（ ）形式。
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境内上市公司所属企业境外上市财务顾问的职责有（ ）。