The histogram to the right represents the weights (in pounds) of members of a certain high-school programming

Question:

The histogram to the right represents the weights (in pounds) of members of a certain high-school programming team.
That is the class width? WIZ are the approximate lower and upper class limits of the first class?
What is the class width?

100 110 120 130 140 150 160 170 Weight (Ibs) kouanbasg

The class width is.....
(Simplify your answer.)
What are the approximate lower and upper class limits of the first class?
The approximate lower class limit is ......
The approximate upper class limit is ......
(Simplify your answers.)