某企业2018年技术工占50%，2019年新招收了一批学徒工，使学徒工的比重增加了10%。假定全厂各级工资水平均无变化，则2019年职工总平均工资将（）

A summary measure that is computed from a sample to describe a characteristic of the population is called（）

The number of phone calls arriving at a switchboard each hour has been recorded and the following frequency distribution has been developed.What is the approximate range of the number of phone calls arriving each hour？（）

常用的长期趋势测定的方法有哪些？各有什么特点？

The number of class intervals in a frequency distribution is usually between （）.

Simon Arnett, Director of Human Resources, is exploring the causes of employee absenteeism at Buderim Bottling during the last operating year (1 January 2005 to 31 December 2005). The average number of absences per employee, calculated from the personnel data of all employees, is a （）.

对全国各铁路交通枢纽的货运量、货物种类等进行调查，以了解全国铁路货运概况。这种调查属于（）

某班的学习按考试成绩分为60分以下，60-70，70-80，80-90，90-100，这种分组（）

什么是季节变动？研究它的意义何在？如何测定季节变动？

If data are grouped into intervals and the number of items in each group is listed, this could be called a （）