4 Let one week's supply and demand functions for gasoline be given by p = D(q) = 288-79 and p= S(q) =7q, where p is the price in dollars and q is the number of 42-gallon barrels. (a) Graph these p= S(q) =9, where p is the price in dollars and q is the number of 42-gallon barrels. (a) Graph these equations on the same axes. (b) Find the equilibrium quantity. (c) Find the equilibrium price. 800 800 (b) The equilibrium quantity is barrels. Enter your answer in the answer box and then click Check Answer.