下列( )选项是main( )方法的返回值类型。
A．int
B．void
C．boolean
D．static
参考答案：B
10．--- Hello, John here, can I speak to Mary , please?
---_____________.
A．Of course, but she is out
B．She will be back in a moment
C．You may leave a message
D．Hold on, please
国网公司有序用电工作的实施原则是什么？
