對(duì)全國(guó)各鐵路交通樞紐的貨運(yùn)量、貨物種類等進(jìn)行調(diào)查，以了解全國(guó)鐵路貨運(yùn)概況。這種調(diào)查屬于（）

企業(yè)生產(chǎn)一種產(chǎn)品需順次經(jīng)過(guò)四個(gè)車間，這四個(gè)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？

One advantage of a stem and leaf plot over a frequency distribution is that （）.

時(shí)間序列構(gòu)成因素有哪些？分解的基本原理和思路是什么？

If the individual class frequency is divided by the total frequency, the result is the （）.

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 cumulative frequency of the third class？（）

A cumulative frequency distribution would provide（）.

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

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). Personnel records of 50 employees are selected for analysis. (The plant employs 250.) For this study, the average number days absent for these 50 employees is a （）.

一個(gè)地區(qū)一定時(shí)期的商品零售額屬于（）