Years Employed	Frequency
1 - 5	5
6 - 10	20
11 - 15	25
16 - 20	10
21 - 25	5
26 - 30	5

List the lower class limits for each class

1. list the upper class limits for each class
2. List the class boundaries for each class
3. List the class midpoints for each class
4. List the class width for each class
5. Construct a BOTH a relative and cumulative frequency distribution