第30题: [单项选择]绞车闸轮磨损深度不大于() A. 2mm B. 3mm C. 4mm D. 5mm 参考答案:A
第31题: [单项选择]熔断器主要用来进行()保护. A. 过载 B. 过电压 C. 失电压 D. 短路 参考答案:D
第32题: [单项选择]Questions 23 to 25 are based on the conversation you have just heard. A. Take some extra time. B. Do a writing exercise. C. Do some work for another course. D. Write the story ending first. 参考答案:B 答案解析:[听力原文] What did the professor tell the woman to do