The demand curve for original Iguanawoman comics is given by
q =
(450 − p)2
50
(0 ≤ p ≤ 450)
where q is the number of copies the publisher can sell per week if it sets the price at $p.
(a) Find the price elasticity of demand when the price is set at $31 per copy.
(b) Find the price at which the publisher should sell the books in order to maximize weekly revenue(c) What, to the nearest $1, is the maximum weekly revenue the publisher can realize from sales of Iguanawoman comics?

NEED HELP ON TEST ASAP! tried 5 times and not working

Question

The demand curve for original Iguanawoman comics is given by
q = 
(450 − p)2
50
      (0 ≤ p ≤ 450)
where q is the number of copies the publisher can sell per week if it sets the price at $p.
(a) Find the price elasticity of demand when the price is set at $31 per copy.
(b) Find the price at which the publisher should sell the books in order to maximize weekly revenue(c) What, to the nearest $1, is the maximum weekly revenue the publisher can realize from sales of Iguanawoman comics?

NEED HELP ON TEST ASAP! tried 5 times and not working