问题 单项选择题

下列度量单位中,用来度量计算机网络数据传输速度(比特率)的是______。

A.MB/s

B.MIPS

C.GHz

D.Mbit/s

答案

参考答案:D

解析:[分析] 计算机的存储速度可用MB/s来度量,计算机运算速度用MIPS来度量,时钟主频用GHz来度量。

阅读理解

阅读理解。

     How to eat healthfully can be especially complex for working women who often have

neither the desire nor the time to cook for themselves (or for anyone else ).Registered

dietitian Barbara Morrissey suggests that a few simple rules can help.

     "Go for nutrient-dense foods,"she suggests,"foods that contain a multiple of nutrients.

For example,select whole wheat bread as a breakfast food,rather than coffee cake. Or

drink orange juice rather than orange drink,which contains only a small percentage of real

juice-the rest is largely colored sugar water. You just can't compare the value of these

foods, the nutrient-dense ones are so superior,"she emphasizes.

     Morrissey believes that variety is not only the spice of life,it's the foundation of a healthful

diet. Diets which are based on one or two foods are not only almost impossible to keep up

the strength,they can be very harmful, she says, because nutrients aren't supplied in enough

amounts or balance.

     According to Morrissey,trying to find a diet that can cure your illnesses,or make you

superwoman is a fruitless search." As women,many of us are too concerned with staying

thin,"she says,and "we believe that vitamins are some kind of magic cure to replace food."

     "We need carbohydrates,protein and fat-they are like the wood in the fireplace. The

vitamins and minerals are like the match,the spark,for the fuel,"she explains." We need

them all,but in a very different proportions(部分). And if the fuel isn't there,the spark is

useless."

1.From the first paragraph we know that working women________.

A.think cooking is especially complicated

B.do not share the same views with registered dietitians

C.are busy and not interested in cooking

D.are likely to eat healthfully

2.Orange juice is different from orange drink because________.

A.it contains only a small percentage of real juice

B.it is natural,nutritious and prepared from real oranges

C.it is largely orange-colored sugar water

D.it produces nothing but calories

3.In Paragraph 4,"a fruitless search" means "____"._____

A.an effort with no results

B.a search for a diet without fruits

C.a research on fruitless diet

D.a diet serving as medicine

4.Many women take it for granted,according to the passage that________.

A.a balanced diet can result in being fat

B.staying thin and healthy are both possible

C.lack of variety in diets leads to staying thin

D.vitamins are some kind of substitutions(代替物)for food

5. By saying "if the fuel isn't there,the spark is useless",the author means "________".

A.carbohydrates,protein and fat are enough to support a human life

B.vitamins and minerals are almost of no value

C.carbohydrates,protein and fat are as important as vitamins and minerals

D.without carbohydrates,protein and fat,vitamins and minerals are of no use

单项选择题