This room is used ______ a reading room. [ ]
A. as
B. for
C. by
D. in
A
一把钥匙只能开一把锁，现在有10把钥匙和10把锁，最多试多少次才能配好全部钥匙和锁( )
A．45次B．40次C．36次D．55次
下面属于A类IP地址的是()。
A．61.11.68.1
B．128.168.119.102
C．202.199.15.32
D．294.125.13.1
