刮削大型精密平板，用平行桥板和分度值为0.02mm/1000mm水平仪测得各段的直线度误差值（见图5），试仿照第六章图6-41作出各段的直线度误差曲线图，求出各测量段的最大误差值，并分析该平板的最大误差集中在哪一段。
参考答案：
求分级尺寸AK1、AK2
因 A0max=A1max-(A2max+A3max+A4max+A5max)-AK1min
故AK1min=105.06mm-(24.97+24.97+24.97+19.97)mm-0.30mm
=9.88mm
分级差为T0-TK=(0.24-0.06)mm=0.18mm
答 调整件分2级，分级尺寸为AK1=
；AK2=
| 阅读理解。 阅读下面短文，根据所读内容在表格中的空白处填入适当单词。注意：每个空格只填一个单词。 | ||||||||||||||||||
| Nowadays more and more people are concerned about their health, but how to keep healthy? Different people may give different answers to this question. In my opinion, it is essential to do the following. First, it is absolutely necessary to take some exercise at regular time every day. Research shows that getting plenty of exercise can make the heart beat faster and the lungs work harder. This strengthens the heart, reduces the chance of heart attack, and helps lower blood pressure. That's why more and more people are becoming active in various kinds of sports and exercise. Every morning many people get up early and take much exercise. Some play ball games while others run, jog, walk or dance to music. In the afternoon, there are also many people keen on sports. Through sports and exercise, people become healthier and stronger. Medical researchers have proved that what people eat affects their health. They advise people to eat more fruit and vegetables and less meat such as beef and pork because meat contains more fat than poultry (家禽) and fish. Fat can build up in the arteries (动脉), block the flow of blood, and cause a heart attack or stroke (中风). Getting rid of bad habits like smoking and drinking alcohol is also an important way to keep healthy. Smoking and drinking alcohol injure one's health a great deal, and therefore should be given up. Unfortunately few people follow this advice.
| ||||||||||||||||||