1. (1.5pts each) For this question suppose that f (x, y) = x-y . Furthermore, suppose the curve C is given by r(1) = (1+12,12 -1) where 1St2 . Find the exact value of each of the following line integrals: (a) |f(x, y)dx (b) [ f ( x, y) dy (c) ] f(x, y)ds