题目

一台理想变压器，原、副线圈的匝数比∶＝20∶1，原线圈接入220V的交流电压，副线圈向一电阻为110W的用电器供电，则原、副线圈中的电流分别为：（ ） A．0.1A，2A B．2A，0.1A C．0.005A，0.1A D．0.1A，0.005A 答案：CJohn had tried to find a job in the sales department, but he had no__________.        A．chance      B．time                C．quality                   D．luck