【简答题】It was very cold last Sunday. Paul and his friends Allen, Bill and Betty went to the lake after breakfast. They began to skate on the ice. Paul skated better than his three friends. He skated fast and...
【单选题】It was last Sunday ______ we saw one of my old friends in the park.
【单选题】It was__last Sunday morning. It rained__.
【简答题】测得工作在放大电路中两个晶体管的三个电极电流如下图所示, 1判断它们各是NPN管还是PNP管,在图中标出e,b,c极; 2估算晶体管的 α 和 β 值。
【简答题】测得工作在放大电路中某个晶体三极管的两个电极电流如图所示。 ( 1 )求另一个电极电流,并在图中标出实际方向。 ( 2 )判断它是 NPN 还是 PNP 型管,标出 E 、 B 、 C 极。 ( 3 )估算它的 β 。
【简答题】从方框中选择合适的选项完成短文。 Last Sunday My class went to the Central Zoo last Sunday. It was our first journey and we were all very happy. 1 Halfway to the zoo we stopped at a station because the driver of the b...
【单选题】如图所示电路中,测得工作在放大状态的某个晶体三极管两个电极电流,则第三个电极的电流大小、方向和管脚自左到右的顺序分别为( )。