问题 单项选择题

在单CPU系统中,关于进程的叙述正确的是( )。

A.一个处于等待状态的进程一旦分配了CPU,即进入运行状态

B.只能有一个进程处于就绪状态

C.一个进程可以同时处于就绪状态和等待状态

D.最多只能有一个进程处于运行状态

答案

参考答案:D

解析:[分析] 由于只有一个处理器,所以某个时刻最多只有一个进程处于运行状态。一个处于就绪状态的进程一旦分配了CPU,即进入运行状态:处于就绪状态的进程可以不止一个,他们都等待处理器的调度;一个进程等待某事件发生时,进入等待状态,不能同时处于就绪状态和等待状态。

解答题
阅读理解

阅读理解。

     LOS ANGELES-The advice offered from any other 82-year-olds might have made young people yawn and

roll their eyes.

     But when former South African President Nelson Mandela advised two dozen Los Angeles to take education seriously, his audience was listening.

     The famed old man said to the young people that if they expected to improve the lives of others in the future, they must work at improving their own lives now."Education is one of the most important weapons you have," Mandela advised,"it will place you in a far better position to serve yourself and your community."

     "The point is, he was young once and rebellious once and he kept his dream alive, just as you each have

dreams." Explained South Africa's ambassador to the United States, Sheita Sisulu, as she introduced Mandela to

the young crowd.

     Asked for specific advice about changing society by 21-year-old Ahmed Younis, Mandela suggested that

somehow helping arouse more American interest in foreign affairs might be a start.

     "There is an impression that Americans, in general, have not followed international developments properly," Mandela said,"I'm not making that statement myself, but there are serious political analysts who say Americans

are not well informed as to what has happened in the world."

     22-year-old Omari Trice said Mandela left him full of passion."He's a person who set the tone for an entire

nation." said Trice.

     "You go away feeling you need to be Superman in order to get things done." Trice said.

1. From the passage, we can conclude that American youth ______.

A. are willing to accept the advice from world-famous leaders

B. usually think that advice from old people is not worth considering

C. have a good understanding of the old

D. have no intention to improve the lives of others

2. Nelson Mandela makes the point in his speech that American youth leaders should _______.

A. improve their own lives

B. go to college for better education

C. put more importance on education

D. become interested in foreign affairs

3. What Sheila Sisulu said suggested that _______.

A. Nelson Mandela never lost hope in his life

B. was especially troublesome when young

C. Nelson Mandela was quite different from American youth when young

D. American youth should be no more rebellious

4. From what Trice said, we can know that _______.

A. he was greatly impressed and encouraged by Mandela's speech

B. he thought little of Mandela's speech

C. he must be a superman in order to change society

D. he'll be more interested in international development