In June 2001 the retail price of a 25-kilogram bag of cornmeal was $8 in Zambia; by December the price had risen to $11. The result was that one retailer reported a drop in sales from 19 bags per day to 7 bags per day. Assume that the retailer is prepared to sell 3 bags per day at $8 and 15 bags per day at $11. Find linear demand and supply equations, and then compute the retailer's equilibrium price