根据所给问句选正确答语。( ) 1. What is Danny doing?( 发布时间:2017-05-04 15:22 │ 来源:www.tikuol.com 题型:补全对话,情景问答 问题: 根据所给问句选正确答语。( ) 1. What is Danny doing?( ) 2. What season is this?( ) 3. What is Jenny doing?( ) 4. What are you learning?A. It's summer.B. She's taking off her dress.C. He's skiing on the snow.D. I am learning English.
题型:补全对话,情景问答 如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,串联在原线圈电路中电流表的示数为1A,下列说法正确的是( )A.变压器输出端所接电压表的示数为20VB.变压器的输出功率为200WC.变压器输出端的交流电的频率为50HzD.穿过变压器铁芯的磁通量变化率的最大值为20/n2Wb/s 查看答案