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Consider a model of a competitive market in which price is adjust to excess demand or supply and firms enter or exit the industry if profits or losses are being made. Price adjusts to excess demand according to P=0(qD-qS), 620 where q"= a+bp is the demand function, q =mN is the supply function, p is price, N is the number of firms in the industry, 0 is speed-of adjustment coefficient. Making these substitutions gives P=0(a+bp-mN). The number of firms adjusts according to N=z (p - C), z>0 where C is the fixed average cost of production. Firms enter (N>0) if price exceeds average cost (positive profits) and exit if price is less than the average cost (negative profit). Solve this system of differential equations for price and number of firms