Juan is a software salesperson. His base salary is $2300 and he makes 70$ more for every copy of History is Fun he sells. His total pay, P (in dollars), after selling copies is c given by the following.

P=2300 + 70c
(a) What is Juan's total pay if he sells 22 copies?
(b) If Juan's total pay is $4610, how many copies did he sell?