— ____ is it?
— It's seven o'clock.[ ]
A. How much
B. How many
C. What time
答案:C
用0到9这10个数字,可以组成没有重复数字的三位数的个数为( )
A.576
B.720
C.810
D.648
下列协议与电子邮件无关的是______。
A.SMTP
B.POP3
C.MIME
D.SNMP