问题 单项选择题

若内存采用固定分区管理方案,在已分配区可能会产生未用空间,通常称之为______。

A.废块

B.空闲页面

C.碎片

D.空闲簇

答案

参考答案:C

解析: 分区存储组织的基本原理是,给每一个内存中的进程划分一块适当大小的存储区,以连续存储各进程的程序和数据,使各进程得以并发进行。根据分区的时机,分区方法可分为固定分区和动态分区两种。 ①固定分区是一种静态分区方式,在系统生成时已将主存划分为若干个分区,每个分区的大小可不等。操作系统通过主存分配情况表管理主存。这种方法的突出问题是已分配区中存在未用空间,原因是程序或作业的大小可能不刚好等于分区的大小,故造成了空间的浪费。通常将已分配分区内的未用的空间叫做碎片或零头。选项C正确。 ②动态分区在作业的处理过程中进行,其大小可随作业或进程对内存的要求而改变。

阅读理解

Parents often believe that they have a good relationship with their teenagers. But last summer, Joanna and Henry noticed a change in their older son: suddenly he seemed to be talking far more to his friends than to his parents. "The door to his room is always shut." Joanna noted.

Tina and Mark noticed similar changes in their 14-year-old daughter. "She used to sit in my arms on the sofa and talk with me," said Mark. "Now we joke that she does this only when she wants something. Sometimes she wants to be treated like a little girl and sometimes like a young lady. The problem is figuring out which time is which."

Before age 11, children like to tell their parents what's on their minds. "In fact, parents are first on the list." said Michael Riera, author of Uncommon Sense for Parents with Teenagers. "This completely changes during the teen years." Riera explained. "They talk to their friends first, then maybe their teachers, and their parents last."

Parents who know what's going on in their teenagers' lives are in the best position to help them. To break down the wall of silence, parents should create chances to understand what their children want to say, and try to find ways to talk and write to them. And they must give their children a mental break, for children also need freedom, though young. Another thing parents should remember is that to be a friend, not a manager, with their children is a better way to know them.

小题1:"The door to his room is always shut" suggests that the son_______.

A.is always busy with his studies

B.doesn't want to be disturbed

C.keeps himself away from his parents

D.begins to dislike his parents小题2:What troubles Tina and Mark most is that _______.

A.their daughter isn't as lovely as before

B.they can't read their daughter's mind exactly

C.they don't know what to say to their daughter

D.their daughter talks with them only when she needs help小题3:which of the following best explains "the wall of silence" in the last paragraph?

A.Teenagers talk a lot with their friends.

B.Teenagers do not want to understand their parents.

C.Teenagers do not talk much with their parents.

D.Teenagers talk little about their own lives.小题4:What can be learned from the passage?

A.Parents are unhappy with their growing children.

B.Parents have suitable ways to talk with their teenagers.

C.Parents should be patient with their silent teenagers.

D.Parents should try to understand their teenagers.

多项选择题