试题四(共15分)阅读下列说明和C代码，回答问题1至问题3，将解答写在答题纸的对应栏

发布时间：2017-07-11 01:46 │ 来源：www.tikuol.com

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问题：

试题四(共15分)阅读下列说明和C代码，回答问题1至问题3，将解答写在答题纸的对应栏内。[说明]用两台处理机A和B处理n个作业。设A和B处理第i个作业的时间分别为a_i和b_i。由于各个作业的特点和机器性能的关系，对某些作业，在A上处理时间长，而对某些作业在B上处理时间长。一台处理机在某个时刻只能处理一个作业，而且作业处理是不可中断的，每个作业只能被处理一次。现要找出一个最优调度方案，使得n个作业被这两台处理机处理完毕的时间(所有作业被处理的时间之和)最少。

[问题1](9分)根据以上说明和C代码，填充C代码中的空(1]～(5)。

考点：计算机软件水平考试中级软件设计师计算机水平考试中级软件设计师2012年上半年下午真题

题型：问答题

阅读理解。

As bananas ripen, the green skin turns yellow gradually. Chemical changes occur in the flesh of the fruit
as well: starch (淀粉) changes to sugar; pectin (果胶) breaks down, losing its stiffness; and the flesh softens.
Is ripening fruit a self-contained system, or is the rate of these changes affected by the environment? We
designed the experiment below to see if different atmospheres, produced by different packaging, affected the
rate of ripening. You will vary the atmosphere surrounding unripe bananas and observe the effect on the ripening
process.

     Now set up the bananas in their
environments as follows:
     1. Put two green bananas in a paper bag
and fold the top over to seal out the air.
     2. Put one green banana and the very
ripe banana in the other paper bag and fold
over the top.
     3. Put two green bananas in a plastic
bag and seal it.
     4. Wrap (包) one green banana tightly
in a plastic bag.
     5. Leave one green banana exposed to
the air.

Leave the fruit alone for four or five days to ripen. Ripening fruit "breathes". This means that it takes up
oxygen and gives off CO₂. Oxygen is extremely important and necessary for the chemical reactions involved
in ripening. In addition, ripening fruit gives off another gas, called ethylene (乙烯). Not only is ethylene a product
of ripening fruit, it also promotes the further ripening of the fruit.
Paper bags tend to keep the ethylene in, but they allow oxygen and ethylene to pass through slowly. Plastic
bags do not allow the free flow of oxygen or ethylene. In this experiment, the green banana in paper bag with
the ripe banana should ripen most quickly. The green bananas in the paper bag should ripen faster than the
bananas in the plastic bag. The banana left exposed to air has an unlimited supply of oxygen, so it will turn brown
most quickly. You will notice that the side of this banana that rests on the counter will ripen more quickly than
the other sides, because it has the closest contact (接触) with its own ethylene. The banana that is tightly
wrapped in plastic has no oxygen supply and should ripen most slowly. Now can you see why bananas are
sealed in plastic in many supermarkets?

1. What makes the green banana in Bag 2 ripen more quickly than the ones in Bag 1?

A. Ethylene from the very ripe banana.
B. The free flow of oxygen or ethylene.
C. CO₂ from the very ripe banana.
D. The limitation of oxygen supply.

2. How can we slow down the ripening of bananas exposed to the air?

A. To rest them on the counter.
B. To keep them in the basket.
C. To put them on the ground.
D. To hang them up from the ceiling.

3. It can be concluded from the passage that _____.

A the ripening banana is a self-contained system
B. the rate of ripening bananas is affected by the environment
C. wrapped bananas experience no chemical changes to ripen
D. ripening bananas give off oxygen, CO₂and ethylene

4. Why are bananas sealed in plastic in many supermarkets?

A. To make them ripen more quickly.
B. To make them ripen more slowly.
C. To make banana flesh soften.
D. To turn green bananas yellow.

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主机循环油泵至少应设置两台，互为备用，其中至少一台为独立驱动泵。

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已知直齿圆柱齿轮全齿高h=10mm，则可求得其齿厚S等于（）mm。

A.3.14

B.6.28

C.4

D.8

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通常药酒饮用的量约为（）

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谐波制动的变压器纵差保护中设置差动速断元件的主要原因是（）。

A.为了提高差动保护的动作速度；

B.为了防止在区内故障较高的短路水平时，由于电流互感器的饱和产生高次谐波量增加，导致差动元件拒动；

C.保护设置的双重化，互为备用；

D.为了提高差动保护的可靠性。

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