find the class width, lower class limit, upper-class limit, class width, class boundaries, and class midpoints.

Class	Frequency (f)
1.5 - 5.5	5
6.5 - 10.5	8
11.5 - 15.5	6
16.5 - 20.5	8
21.5 - 25.5	5
26.5 - 30.5	4