1. (a) (7pts) Find and sketch the domain of the function f(x, y) = In(4 -x2 -y?). 24 (b) (8pts) Show that lim (z,y) +(0,0) x4 + 1/2 does not exist. 2. (a) (8pts) z= ery, x = s' - th, and y = 2st. Find _ and at (b) (7pts) Let z = f(xy, y). Find axdy