Question 19 There are 2 customers in the economy of exchange. The 2 consumers have linear utility function in commodity v. When commodity X's amounts in quantity are calculated horizontally and the amounts in quantity of commodity y are calculated in vertical direction of the edgeworth box. The pareto efficient allocations' set contains a; [vertical line, a straight line starting from bottom left to the right upper edge, a curved line starting from bottom left to the right upper edge, all the edges of the box, or a straight line that is horizontal in the box]. Select one option in the parenthesis, elaborate with at least 50 words