问题 解答题

小东拿着一根长竹竿进一个宽为3米的城门,他先横着拿不进去,又竖起来拿,结果竹竿比城门高1米,当他把竹竿斜着时,两端刚好顶着城门的对角,问竹竿长多少米?

答案

解:由题意得:设城门高为x米,

则(x+1)2=x2+32

解得:x=4,

∴竹竿长为4+1=5米。

填空题
阅读理解

阅读理解。

      No matter what your reasons for eating more vegetarian food are, there is no denying the

obvious health benefits that result from the elimination (排除) of red meat from your diet. In

general, vegetarians have lower levels of blood fats,  cholesterol  (胆固醇) and  triglyceride 

 (甘油三酸脂) than meat eaters of a similar age and social status.

      High levels of blood fats are associated with an increased risk of heart disease. Lacto-ovo

vegetarians (乳类蛋类素食者), who eat eggs and dairy products, have higher cholesterol levels

than vegans  (绝对素食者). Even among lacto-ovo vegetarians, however, cholesterol levels

are generally lower than they are among meat eaters.

      Researchers have found that older men that eat meat six or more times a week are twice as

likely to die of heart disease as those that don't have meat. Among middle-aged men, meat eaters

were four times more likely to suffer a fatal heart attack, according to the study.

      As for women, who are partly protected by their hormones and generally develop heart disease

later in life than men, the risk of fatal heart disease has been found to be lower only among older

vegetarians. In a 1982 study of more than 10 000 vegetarians and meat eaters, British researchers

found that the more meat people consumed, the greater risk they had of suffering a heart attack.

      Though eliminating meat from the diet is likely to reduce your consumption of heart-damaging

fats and cholesterol, continuing to eat large amounts of high-fat dairy products and cholesterol-rich

eggs can reduce the benefit. The introduction of more vegetables, fruit and raw foods will definitely

enhance the benefits of giving up eating meat.

1. According to the passage, vegetarians are healthier than meat eaters in all of the following aspects

EXCEPT their_________.   

A. heart rate                

B. cholesterol levels

C. triglyceride levels        

D. blood fat levels

2. We can learn from the underlined sentence in the first paragraph that__________.    

A. you need to have a good reason for having vegetarian food

B. eliminating red meat from your diet is no good for your health

C. eating more vegetarian food can have obvious benefits for your health

D. the possibility of meat eaters developing heart disease is twice as high as that for vegetarians

3. From the second paragraph, we can know that   

A. lacto-ovo vegetarians have the healthiest diets

B. vegetarians don't eat eggs and dairy products

C . vegans have the lowest cholesterol levels

D. vegans do not have the risk of catching heart disease

4. What can we learn from the passage?      

A. Women tend to suffer from heart disease earlier men.

B. Older women have less chance of suffering from heart disease than young women.

C. Eating more meat may increase a person's chance of developing heart disease.

D. Eating meat has little influence on older people's health.