a. T(u,v)=(g(u,v),h(u,v)),x=g(u,v)=2u−v, and y=h(u,v)=u+2v. The functions g and h are continuous and differentiable, and the partial derivatives gu(u,v)=2, gv(u,v)=−1, hu(u,v)=1, and hv(u,v)=2 are continuous on S; b. T(0,0)=(0,0), T(1,0)=(2,1), T(0,1)=(−1,2), and T(1,1)=(1,3); c. R is the sqaure of vertices (0,0),(2,1),(1,3),and(−1,2) in the xy-plane; see the following figure.
