A cumulative frequency polygon is also called （）.

一個地區(qū)一定時期的商品零售額屬于（）

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

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 （）.

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

要了解某地區(qū)全部大學(xué)生的就業(yè)情況，那么（）

某班的學(xué)習(xí)按考試成績分為60分以下，60-70，70-80，80-90，90-100，這種分組（）

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

以2000年a0為最初水平，2016年an為最末水平，計算鋼產(chǎn)量的年平均發(fā)展速度時，須開（）

One rule that must always be followed in constructing frequency distributions is that （）.