In a certain kingdom, the demand function for rye bread was q = 181 - 8p and the supply function was q = 13 + 6p, where p is the price in zlotys and q is loaves of bread. The king made it illegal to sell rye bread for a price above 6 zlotys per loaf. To avoid shortages, he agreed to pay bakers enough of a subsidy for each loaf of bread so as to make supply equal demand. How much would the subsidy per loaf have to be?