A perfectly competitive industry has a large number of potential entrants. all firms have identical cost structure and minimize cost at the same point where Min AC=MC. if MC=q and STC=0.5q2+50 find the quantity and the cost at that point. if total market demand is P=30-1/30Q, derive the short run market of supply curve and find the industry equilibrium quantity and price. if the demand shifts to P=60-1/30Q what will be the new market equilibrium price and quantity? what will be the output/firm in the short run? Since the long run cost has to be at the minimum AC how much should the market supply be? What’s the new number of firms needed in this quantity?