问题 单项选择题

5英寸磁盘,最小磁道的直径为4厘米,最大磁道直径为8厘米,每分钟10000转,共有20记录面,每个记录面有8000个磁道,每条磁道上有511个扇区,每个扇区实际记录有600个字节,其中有效数据为512个字节。则这个磁盘存储器的有效存储容量是 (6) GB,磁道密度是每毫米 (7) 条磁道。

(7)处填()。

A.350

B.400

C.800

D.200

答案

参考答案:B

阅读理解

阅读理解。

     A shocking number of children are overweight and obese, and doctors are seeing increasingly high levels

of cholesterol (胆固醇) in children, even those with no family history of high cholesterol. To help your kids

maintain a healthy diet and healthy cholesterol levels, you need to do the following.

     Pack their lunches

     That way you can at least try to ensure they get something healthy instead of the fried and starchy (富含

淀粉的) food that dominate most school cafeterias. The three most common food ordered in elementary

school cafeterias are ground beef (碎肉), chicken nuggets (鸡肉块) and cheese.

     Limit fast food

     Set a limit of no more than one or two fast-food meals a month, and when you do make a fast-food visit,

push the salads, plain baked potatoes, and broiled chicken. If the kids must have hamburgers, order them

without cheese.

     Forget white

     White bread, white rice, white pasta, that is. Serve them peanut butter and jelly on whole wheat bread and

meatballs on whole wheat pasta.

     Make it easy

     Cut up a bowl of fruit and put is before your TV-gazing kids. They'll eat it as if it were popcorn (爆米花).

Better yet, turn the TV off and serve the fruit to them after they've finished a bike ride around the block.

     Set an example

     The best way to make sure your kids live a heart-healthy lifestyle is to live one yourself. That could be

more rewarding to see benefits not only to your cholesterol, but to your children's as well.

1. The underlined word "obese" in the first paragraph means "____".

A. very short

B. very tall

C. very thin

D. very fat

2. According to the passage, parents should encourage kids to eat ____.

A. fried and starchy foods that most school cafeterias mainly serve

B. more than one or two fast-food meals a month

C. fruit instead of popcorn

D. as mush white food as possible

3. According to the passage, the underlined word "one" in the last paragraph refers to ____.

A. an example

B. a heart-healthy lifestyle

C. a kid

D. a kind of food

4. The main purpose of this passage is to ____.

A. advise parents how to keep their children healthy

B. tell parents how to set an example to their children

C. tell kids the best way to lose weight

D. tell kids how dangerous overweight is

单项选择题