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问题 单项选择题 A1型题

计算2007年某地的婴儿死亡率，分母应为2007年（）

A.年初0岁组人口数

B.年中0岁组人口数

C.年末0岁组人口数

D.活产数

E.平均人口数

答案

参考答案：D

解析：

婴儿死亡率指某年某地活产儿中不满1周岁婴儿的死亡频率。计算公式为：，故选项D正确。

单项选择题

One of the biggest threats to a company’s productivity is absenteeism. Studies have shown that companies with in-house childcare programs see fewer absences among their employees who are parents than companies without such programs. Therefore, many companies could boost their productivity by starting in-house childcare programs.
Which of the following, if true, most weakens the above argument ？（）

A. Companies that reimburse outside childcare programs actually see less absenteeism among working parents than companies with in-house programs.

B. In-house childcare programs create distractions for nonparents that can harm their productivity.

C. Absenteeism is not a serious problem for companies that impose harsh penalties on employees who miss work.

D. Studies have shown that employees with children are more likely than those without children to remain in the same job for more than five years.

E. Potential employees generally view companies with in-house childcare programs as more desirable places to work than companies without such programs.
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单项选择题

水准仪和经纬仪的十字丝分划板都有上.下两条较短的横丝可以用来测量距离，称为（）。

A.水平丝

B.视距丝

C.十字丝

D.高差丝
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