Suppose the demand curve for a product is given by Q = 300 - 2P + 4I, where "I" is the average income measured in thousands of dollars. The supply curve is Q = 3P - 50.

a) If I = 25, find the market-clearing price and quantity for the product.

b) If I = 50, find the market-clearing price and quantity for the product.

c) Draw a graph to illustrate your answers.