Consider a trade economy with two people (A and B) and two goods (1 and 2). Person A's utility function is U A = x1x2 where xi is A's consumption of good i ∈ {1, 2}. Person B's utility function is U B = y1y 2 2 , where yi is B's consumption of good i ∈ {1, 2}. There are 30 units of each good in the economy. Which of the following allocations are efficient?