Determine the heat energy received per kilogram of steam produced

I've never been good at math he told he loves but he keeps cheating on me, so it ain't adding up sis

1. the following set of data represents the number of waiting times in minutes from a random sample of 30 customers waiting for service at a department store. 4 5 7 10 11 11 12 12 13 15 15 17 17 17 17 17 18 20 20 21 22 22 23 24 25 27 27 31 31 32 a. determine the number of classes and class interval.

The perimiter of a rectangle is 70 inches the legneth of the rectangle is 5 less than 3 times the width of the rectangle what is the width of the rectangle