This is just algebra need some help 10 pts each, will give brainliest Find z if

Thank You!

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.

5500 dollars is placed in an account with an annual interest rate of 6.5%. to the nearest tenth of a year, how long will it take for the account value to reach 19700 dollars?

Which is the completely factored from of xy^3-x^3y