Question 2 The function P(z) = -1.5 + 925z - 7000 gives the profit when z units of a certain product are sold Find a) the profit when 85 units are sold dollars b) the average profit per unit when 85 units are sold dollars per unit c) the rate that profit is changing when exactly 85 units are sold dollars per unit d) the rate that profit changes on average when the number of units sold rises from 85 to 170. dollars per unit e) The number of units sold when profit stops increasing and starts decreasing. ( Round to the nearest whole number if necessary.) units