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问题 单项选择题

水准测量中要求前后视距距离大致相等的作用在于削弱地球曲率和大气折光的影响，还可削弱下述中的（）项影响。

A.水准管轴与视准轴不平行的误差

B.十字丝横丝不垂直于竖轴的误差

C.读数误差

D.圆水准器轴与竖轴不平行的误差

答案

参考答案：A

解析：前后视距相等可以在高差计算中消除水准管轴与视准轴不平行的误差

单项选择题

对将要进行离子氯化的工件，入炉前工件（）

A.允许有少量锈，但应无油

B.干净无锈，无油

C.允许有少量铁锈和油污

D.允许有少量油污，但不得有铁锈
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单项选择题

A woman tells the nurse that her 6-year-old daughter has severe nosebleeds. Which of the following instructions should the nurse give this woman to manage nosebleeds

A．Help the child assume a comfortable position with her head tilted backward.

B．Tilt the child's head backward and place firm pressure on the nose.

C．Help the child lie on her stomach and collect the blood on a clean towel.

D．Place the child in a sitting position with her neck bent forward and apply firm pressure on the nasal septum.
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