问题 单项选择题

某水道上空有大桥,其净空高度为24m,某轮吃水7.5m,主桅高22m,型深9.8m,与桥的安全余量1m,该大潮升5.3m,则可安全通过该水道的最大潮高为()。

A.4.2m

B.3.8m

C.4.0m

D.4.5m

答案

参考答案:C

选择题
阅读理解

Until a century ago, bloodletting was used to treat many ailments. Dating back to before the time of Christ, the treatment involved letting a type of worm, called a leech, such blood from the patient. People believed that there were liquids called humors in the body and that these determined a person’s personality and heath. Bloodletting, they thought, restored a balance to these humors.

At the time, little was known of the working of the human body, but people did know that the same liquid, blood, flowed throughout everyone’s body. They knew it was a vital substance, for loss of any great amount of it meant certain death. Thus, they concluded that all diseases were carried in the bloodstream, and that if the body was relieved of bad blood, heath would return. Bloodletting, however, came to be used as a cure-all. Woman were bled to keep them from blushing while members of the clergy were bled to prevent them from thinking sinful and worldly thoughts.

From the 11th to the 18th centuries, barbers were the people to go to if you needed to be bled. This custom explains the significance of the traditional barber’s pole: the white stripes stand for bandages and the red stripe for blood.

1. This passage is concerned about            .

healthy people and doctors                         B. bleeding as a cure-all

C. barbers of long ago                                      D. leeches with special jobs to do

2. The red and white stripes on barber pole symbolize         .

sin and redemption                             B. the bleeding form

C. women who are nurses                                  D. humors in the body

3. Why is bloodletting no longer considered a cure-all?

Because more is known about the workings of the human body.

Because leeches were outlawed

Because barbers were too busy cutting hair.

Because today we know that blood is necessary for health

4. In the second paragraph, the word “Thus” could be replaced by the word       .

A. When                        B. However                  C. If                            D. So

5. Ailments means           .

A. cures                         B. women                     C. disease                     D. medicines