问题 单项选择题

影响紧固件力分布的主要因素哪个是错误的()?

A、沿传力路线的紧固件越多,紧固件力分布的不均匀性越大;

B、紧固件间距和紧固件刚度越大,则紧固件力分布的不均匀性越大;

C、被连接件宽度和材料都相同的情况下,若两被连接件的厚度相等,则紧固件力的分布是对称的;

D、无论连接件厚度相不相等,紧固件力的分布都是对称的。

答案

参考答案:D

阅读理解

Last summer, when Amanda R of Anaheim Hills, California, was running on a cross-country course with her team, she blacked out. “I got really dizzy,” she says. “I was out for a few minutes.” At first, Amanda thought she was just tired and didn’t think she had a health problem. She did go to the emergency room, where she was fine after tests, but she fainted (昏厥) again several days later as she was talking with her coach. Another doctor guessed that Amanda had blacked out “because we were in heat so much with not enough water and not enough of the right kind of foods”.

Teens often don’t want to stop and take a break or don’t notice when they start to feel bad, doctors say. However, paying attention if you’re not feeling well is important, as Amanda learned.

As a result, Amanda has changed her habits. “I drink a lot more water,” she says. “And put more salt in my diet. I’m eating more balanced meals.” Amanda advises teen athletes to trust their coaches and speak up when they’re not feeling well. “And recognize the difference between when you’re tired and when there’s something really wrong.”

Some people - up to 3 percent of the population - sweat too much, even in cold weather. The condition, called hyperhidrosis (多汗), can affect many parts and it often runs in families - hands down from generation to generation. Too much sweating over the whole body could be a symptom of another medical condition. Doctors aren’t sure what causes hyperhidrosis, but using special medications or other treatments can help.

小题1:What caused the happening mentioned in the passage during Amanda’s running?

A.She couldn’t breathe in enough air in the race.

B.She didn’t eat anything before the race.

C.She had been running all summer without a rest.

D.She neither drank enough water nor ate enough of the right kind of foods.小题2:What can we infer from Paragraph 4?

A.There is no need to worry when sweating too much, even in cold weather.

B.Hyperhidrosis may have a bad effect on your health.

C.Doctors have discovered why people get hyperhidrosis.

D.Hyperhidrosis is a serious disease and no treatment can help.小题3:The purpose of writing this passage is to____________.

A.tell teens the proper ways to take exercise in summer.

B.tell teens not to run in hot summer.

C.tell teens to pay attention to hyperhidrosis in the summer exercise

D.tell teens how to keep healthy.

单项选择题