问题
单项选择题
防腐绝缘层是以增加金属腐蚀电池()减小电流来控制腐蚀的
A、电压
B、回路电阻
C、电流
答案
参考答案:B
防腐绝缘层是以增加金属腐蚀电池()减小电流来控制腐蚀的
A、电压
B、回路电阻
C、电流
参考答案:B
Daniel has many friends. They look different and they have different personalities, but they are all friendly and helpful. He’d like to introduce some of them to us.
小题1:How many friends does Bob introduce in this passage?
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