最早出现的欧洲货币是() ["欧洲英镑","欧洲法郎","欧洲美元","欧洲马克"]
引发赤潮的污染物主要为() ["重金属盐","氮、磷营养物","固体废弃物","泄露的石油"]
圆桌中心摆成花坛,花坛的高度()客人落座后平视的高度。 ["A、不得高于","B、高于","C、不得低于","D、低于"]
自我推销首先必须()。 ["A、自信","B、有高人一等的心理","C、自傲","D、自爱"]
车速表允许误差范围是() ["A、+40%~-50%","B、+30%~-50%","C、+50%~-50%","D、+20%~-50%"]
测量配线绝缘时兆欧表的使用有何规定?