常规的折射仪只能测试小于（）折射率的宝石。A.1.50 B.1.60 C.1.70_爱下问搜题

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问题单项选择题

常规的折射仪只能测试小于（）折射率的宝石。

A.1.50

B.1.60

C.1.70

D.1.80

答案

参考答案：D

选择题

He got seriously ill. Later he couldn’t see anything at all --- he was ________ blind.

A．nearly

B．especially

C．probably

D．totally

名词解释

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