Consider the following problem. minimize z = 3x1 + 2x2 + 7x3 subject to x1 + x2 = 10 2x1 x2 +x3 10 x1 0, x2 0, x3 0 (a) Write the dual of this problem. (b) Solve the dual problem. (c) Using duality theory obtain the optimal solution of the primal