电信用户通过短信方式发起交费助手代扣的指令是()。
A.WYCZ+任意金额
B.WYCZ+整数金额
C.WYCZ+整数金额(单笔金额需≤3000元)
参考答案:C
While having our dinner, _______.
A.the door bell rang
B.our newspapers came to the door
C.we heard the door bell ringing
D.the postman brought several letters to us
目前,我国采用以()为基础的法定计量单位。
A.公制
B.美制
C.英制
D.国际单位制