Please help me out on this! Would be greatly appreciated

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.

Me with this one question, and i'll upvote the brainliest answer

Joanie watched 1 out of three of a movie in the morning