运行中的GIS发现有异常响声属于（）缺陷。
A.一般缺陷
B.重大缺陷
C.紧急缺陷
D.其他
参考答案：C
某主机的IP地址为220.117.131.12/21，其子网掩码是 (28) 。
A．255.255.248.0
B．255.255.240.0
C．255.255.252.0
D．255.255.255.0
— I think he is taking an active part in social work.
— I agree with you . [ ]
A. in a way
B. on the way
C. by the way
D. in the way
