申请从事普通机动车驾驶员培训的驾驶操作教练员总数的()应当经全国统一考试合格。 ["A.60%","B.70%","C.80%","D.90%"]
井下哪些地点应装设局部接地极?
申请从事普通机动车驾驶员培训的驾驶操作教练员年龄不超过()周岁。 ["A.50","B.55","C.60","D.65"]
申请从事普通机动车驾驶员培训的,理论教练员总数的()应当经全国统一考试合格。 ["A.50%","B.60%","C.70%","D.80%"]
汽车轮胎气压过低会导致()。 ["A.胎体变形增大","B.胎面接地面积增大,磨损加剧","C.材料过度拉伸,易产生胎冠爆裂","D.滚动阻力大,油耗增加"]
哪些地方可以使用有接头的钢丝绳?