Which of the following is best to show the percentage of a total budget that is spent on each category of items？（）

某廠某年職工勞動生產(chǎn)率為20000元，是歷史最高水平的1.2倍。這里的1.2倍是（）

A student achieves an 82 on the first test in a statistics course. From this, she assumes that her average at the end of the semester (after other tests) will be about 82. This is an example of （）.

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

變量數(shù)列中，各組頻率之和應(yīng)（）

時間序列構(gòu)成因素有哪些？分解的基本原理和思路是什么？

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 （）.

企業(yè)生產(chǎn)一種產(chǎn)品需順次經(jīng)過四個車間，這四個車間的廢品率分別為1.5%、2.0%、2.0%和1.0%。該企業(yè)生產(chǎn)這種產(chǎn)品的平均廢品率是多少？

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？（）

品合格率指標是（）