问题
单项选择题
电泳仪输出的是()。
A.直流电
B.正弦交流电
C.方波
D.直流脉冲
答案
参考答案:A
电泳仪输出的是()。
A.直流电
B.正弦交流电
C.方波
D.直流脉冲
参考答案:A
选词填空。 | |
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