solve the following problem involving pareto efficiency

ASSIGNEMENT : 2 Individuals with fixed amounts of goods xand y, i.e. x & y Max U (x ) +y s.t 1.U2(X2) + yz = U 2. X+x = x 3. y ty, = ySuppose a competitive industry consists of M identical firms, each with a cost function; C(y) = y +1. Suppose also that market demand is given by P = 100-Y . Calculate the equilibrium number of firms in the market