In the following integrals, change the order of integration, sketch the corresponding regions, and evaluate the integral both ways. a) 1 0 7 xy dy dx 7x g. b) x/2 0 cos(θ) 0 cos(θ) dr dθ.c) 1 0 2 - y 1 (x + y)2 dx dyd) b a y a f(x, y) dx dy. Let dG/dy = F(y, y) - F(a, y) and F/x = f(x, y). A. G(y) - G(a).B. F(y) - F(a).C. G(b) - G(a).D. G(a) G(b).E. F(b) Fa)