试题与答案

以下物质中,在空气中以气体形式存在的是()A.汞 B.二氧化硫 C.乙酸乙酯 D.氯

题型:单项选择题

题目:

以下物质中,在空气中以气体形式存在的是()

A.汞

B.二氧化硫

C.乙酸乙酯

D.氯乙烯

E.二氧化硅

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A, B解析: 请求宣告专利权无效的理由[详解] 《专利法实施细则》第65条第2款:“前款所称无效宣告请求的理由,是指被授予专利的发明创造不符合专利法第2条、第20条第1款、第22条、第23条、第26条第3...

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