Ann has 10 units of good x and 3 units of good y. Bob has 4 units of good x and 8 units of good y. At these endowments, the marginal rate of substitution (of good x for good y) of Ann and Bob are respectively MRSA (10, 3) = 4 and MRSB (4, 8) = 2. Represent this allocation with an Edgeworth box. Is this allocation efficient? Explain. If not, illustrate the allocations that make both Ann and Bob better off