支气管肺癌常见的早期症状是
A．声音嘶哑B．胸痛C．气促D．呛咳E．发热
参考答案：D
变压器中初级绕组和次级绕组绕在同一铁心上的目的是（）.
A、减小磁滞损耗
B、减小涡流损耗
C、减小漏磁损失
D、减小绕组的铜损
Mary did do some bad things about me, but I have ________ her for that.[ ]
A．regretted
B．freed
C．relaxed
D．forgiven
