(1 point) Suppose that x and y are functions of t defined near x = 1, y = 1, t-1 by the equations x2-9txy + 2y3--6 and da dt Then the value of att1 is (a)-65 (b)-69 (c) -53 (d)-56 (e)-60 Select your answer? ? Do not check your answer with the ? showing. It will be marked wrong.