题目

 曲线在(1,1)处的切线方程是（     ）                                                     A. B.    C.  D. 答案：    B  — Can you go shopping with me this evening, Andy?— ______. I have to study for my math test.A.Yes, I can.B.No, I can’t.C.Sure, I’d love to.D.Sorry, I can’t.