控制格式I/O的操作中，( )是设置域宽的。
A．WS
B．cot
C．setfill()
D．setw()
参考答案：D
— was Gina born?
—She was born July 23rd, 2002.
A．When; on
B．What time, at
C．Where; in
D．Where; on
计量系统安全措施主要为了保证什么？
