There are three firms in the package delivery business. Firm 1 has a total cost curve given by2 1 1 1 1( ) .1 40C Q Q Q= where Q is measured in packages delivered per day. Firms 2 and 3 have identical costs to each other but different than firm 1. In particular, the total cost curve is2 ( ) .25 100j j jC Q Q= (j = 2 or 3). The daily demand is given by QD = 215 - P