下列哪一项不是紫外-可见分光光度计的主要部件()。
A.光源
B.单色器
C.吸收池
D.反光镜
E.检测器
参考答案:D
A.镜面是亮的,而白纸是暗的
B.镜面是暗的,而白纸是亮的
C.镜面和白纸都是暗的
D.镜面和白纸都是亮的
The proportion of women among students enrolled in higher education programs has increased over the past decades. This is partly shown by the fact that in 1959, only 11 percent of the women between twenty and twenty-one were enrolled in college, while in 1981, 30 percent of the women between twenty and twenty-one were enrolled in college. To evaluate the argument above, it would be most useful to compare 1959 and 1981 with regard to which of the following characteristics
A.The percentage of women between twenty and twentyone who were not enrolled in college.
B.The percentage of women between twenty and twentyfive who graduated from college.
C.The percentage of women who, after attending college, entered highly paid professions.
D.The percentage of men between twenty and twenty-one who were enrolled in college.
E.(E) The percentage of men who graduated from high school.