单项选择题
One rule that must always be followed in constructing frequency distributions is that （）.
A.the number of classes must be less than 10 B.each data point can only fall into one class C.the width of each class is equal to the range D.the number of intervals must be an odd number
单项选择题 One advantage of a stem and leaf plot over a frequency distribution is that （）.
单项选择题 The number of class intervals in a frequency distribution is usually between （）.
单项选择题 A cumulative frequency polygon is also called （）.
