Which of the following statements is not true？（）

要了解某地區(qū)全部大學生的就業(yè)情況，那么（）

最能反映離散程度的指標是（）

什么是季節(jié)變動？研究它的意義何在？如何測定季節(jié)變動？

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？（）

變量數列中，各組頻率之和應（）

在組距數列中，下限就是（）

某企業(yè)2018年技術工占50%，2019年新招收了一批學徒工，使學徒工的比重增加了10%。假定全廠各級工資水平均無變化，則2019年職工總平均工資將（）

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 （）.