Suppose that the weekly sales volume y (in thousands of units sold) depends on the price per unit (in dollars) of the product according to the following formula.

y = 31(3p + 1)−2/5, p > 0

(a) what is the rate of change in sales volume when the price is $23? (round your answer to three decimal places.)

dy
dp
=?

(b) interpret your answer to part (a). (round your answer to the nearest whole number.)

if the price increases $1, the sales volume will decrease by ?