–It is snowing heavily again in the north of China and the farmers suffer great loss.

–______ to people in the north, we’re lucky without a cold winter.

A．Comparing

B．If comparing

C．Compared

D．Bing compared

收音机中的调谐电路的线圈的自感系数为L，光在真空中的光速为c,要想接收波长为λ的电台信号，应把调谐电路中的电容调至（     ）

A．

B．

C．

D．