有50人去春游，需要租船，大船每条24元，限乘6人，小船每条20元，限乘4人，怎

下列关于实验现象的描述，正确的是

A．蜡烛在氧气中燃烧产生大量的白烟

B．木炭在空气中燃烧呈红热状态

C．铜片在空气中加热表面变成红棕色

D．镁带在空气中燃烧发出耀眼的白光并生成黑色固体

出口普通货物运输包装容器的报检提供单据有( )

A．出口运输包装容器生产质量许可证

B．“出境货物运输包装检验申请单”

C．包装容器规格清单

D．该批包装容器的设计工艺、材料检验标准等技术资料

Anne Sewell Young was born on January 2, 1871, in the United States. She earned her bachelor’s degree in 1892 from Carleton College in Minnesota, where she also completed a master’s degree in 1897. She went on to earn a PhD (something very unusual for women in those days) from Columbia University in 1906.

Anne Sewell Young was the most famous of the early astronomy students at Carleton College, and one of the few professional women astronomers of her days. Carleton produced half a dozen professional women astronomers in the first 50 years of the course, but she was the only one whose name was recorded in the college’s “Who’s Who”(名人录)

Anne Sewell Young was a number of the AAVSO(美国变星观测者协会). She handed in over 6,500 observations over a 33-year period, and was also one of the first AAVSO Council members.

In 1881, Mt. Holyoke College set up the John Payson Williston Observatory (天文台), and in 1899 Young was named its director. In 1903, a library and a lecture room were added to the observatory building, and in 1907 astronomy was made a course in which one could major at the college, with Yong serving as Department Chair. She retired in 1936, and Alice Farnsworth succeeded her.

Young continued to work on astronomy, publishing her last paper in 1942. She died on August 15, 1961, in California.

68.   Put the following events in the correct order.

a.      Young graduated from Columbia University.

b.      Young served at Carleton College.

c.      Young served as Department Chair.

d.      Young publish her last paper.

A. b, a, c, d                 B. c, b, d, a

C. b, c, d, a                 D. b, d, a, c

69. From the passage we learn that Carleton College made great contribution to      .

A. “Who’s who”

B. astronomy

C. the AAVSO

D. Mt. Holyoke College

70. What is the author’s attitude toward Anne Sewell Young?

A. Negative       B. Neutral       C. positive.      D. We don’t know.

离心式鼓风机的基本方程中ρ（u₂²-u₁²）/2一项表示什么？（）

A.气体在叶轮中静压的增加量

B.由于离心力的作用使静压的增加量

C.由于相对速度降低使静压升高量

D.气体在叶轮中的动压的增加量