对数据元素序列(49,72,68,13,38,50,97,27)进行排序，前三趟排序

患者，男性，56岁。右肘关节疼痛3个月来诊；查体：右前臂近肘关节外侧压痛，右肘关节活动自如，局部未见明显红肿及静脉怒张。

该检查显示左肺门增大，右侧膈肌拾高，纵隔向左侧移位，肺内首先考虑（）

A.转移瘤

B.周围型肺癌

C.中央型肺癌

D.支气管扩张

E.肺结核

I’d like to buy a house ---modern, comfortable, and ____ in a quiet neighborhood.

A．in all

B．at all

C．after all

D．above all

Believe it or not，optical illusion can cut highway crashes.
Japan is a case in point．It has reduced automobile crashes on some roads by Rearly 75 percent using a simple optical illusion．Butst．ripes,called chevrons(人字形)，painted on ther rads make drivers think that they are driving faster than they really are，and thus drivers slow down.
Now the American Automobile Association Foundation for Traffic Safety in Washington D．C. is planning t。repeat Japan’s success．Starting next year，the foundati。n will paint cheyrons and。ther pattems of stripes on selected roads around the country to test how well the patterns reduce highway erashes．
Excessive(too great)speed plays a major role in as much as one fifth of all fatal traffic accidents， according to the foundation．To help reduce those accidents，the foundation will conduct its tests in areas where speed-related hazards(danger)are the greatest curves，exit slopes，traffic circles，and bridges．
Some studies suggest that straight，horizontal bars painted across roads can initially cut the average speed of drivers in half．However,traffic。ften returns to full speed within months as driVers become used to seeing the painted bars．
Chevrons，scientists say，not only give drivers the impression that they are driving faster than they reallv are but als0 make a lane appear to be narrower．The result is a longer lasting reduction in highway speed and the number of traffic accidents．

The passage mainly discusses______.

A．a new way of highway speed control
B．a new pattern for painting highways
C．a new way of training drivers
D．a new type of optical illusion

带电作业工具使用前应根据（）负荷校核机械强度，并满足规定的（）系数。