87 A manufacturer determines the relationship between the demand and price for an item is given by 2x 6xp 30p 125 000 where x is the number of items demanded each month at a price of p dollars each If the price per item is increasing at a rate of 3 50 per month find the rate of change of the demand with respect to time when the price is 50 per item Interpret your answer Round to the nearest integer if necessary