题目

—Excuse me, sir, ________    —I’d like a cup of coffee and two pieces of bread.      A. what do you want?       B. may I have your order?      C. this table is reserved.           D. I would like to serve you. 答案：B如图所示电路中，电阻R为6Ω，小灯泡上标有“6V 2W”，当开关闭合时，小灯泡正常发光．请求出与电路有关的5个物理量．