问题 单项选择题

进程所请求的一次打印输出结束后,将使进程状态从

A.运行态变为就绪态

B.运行态变为等待态

C.就绪态变为运行态

D.等待态变为就绪态

答案

参考答案:D

解析: 运行中的进程有3种状态:运行状态、就绪状态和等待状态。
运行状态:是指进程已获得CPU,并且在CPU中执行的状态。就绪状态:是指进程已具备运行条件,但由于没有获得CPU而不能运行所处的状态,一旦CPU分配给它,就可以运行。等待状态:是指进程因等待某种事件发生而暂时不能运行的状态。例如,当两个进程竞争使用同一资源时,没有占用该资源的进程便处于等待状态。它必须等到该资源被释放后才可以去使用它。引起等待的原因一旦消失,进程就变为就绪状态,以便在适当的时候投入运行。

完形填空

Kids in the Kitchen

Some experts serve up some of the factors that make cooking with kids a pleasure rather than a struggle.

__小题1: 

For obvious reasons, a grown-up needs to be in charge of the stove, sharp knives and electrical equipment.Dr.Colker advises parents to be watchful, even when their kids are involved in relatively safe tasks.The bottom line is to stay close by, and teach your kids to respect basic safety rules.

Leave Time

__小题2:  When kids help, you’ll need extra time to teach them some skills.When  you're in a hurry, give your kids tasks that don't require much guidance.As they get  older and develop more skills, they will become wonderful helpers and even save your  time!                                                                                           

Go for Variety                                                                                    

Our experts agree that children can enjoy more than the usual "kid food", such as chicken nuggets and pizza.__小题3:  Sandra K.Nissenberg suggests exploring the produce passage in the supermarket and talking about the unusual fruits and vegetables you find.

Involve Kids in Clean-up and Table-setting

Dr.Laura Colker reminds parents that preschoolers are eager to deal with grown-up tasks.They actually "enjoy the clean-up and table-setting activities", she says.__小题4:__

They may also enjoy setting the table and counting the spoons.

Make Cooking a Learning Adventure

Cooking helps kids develop a healthy interest in the lifelong challenge of eating nourishing(有营养的), delicious meals.Kids learn about science when they heat or cool a mixture and observe how it changes. 小题5:  And as they wait for the timer to ring, they develop a better understanding of the concept of time

A.Most young children can easily handle simple kitchen equipment

B.Cooking with young children requires patience.

C.Measuring ingredients teaches kids about fractions(分数).

D.Kids can and should help wash and dry the pots and pans.E.Keep an Eye on Safety

F.Stay Equipped

G.To introduce new foods, involve your kids in menu planning and shopping

解答题