a. Find a field G = P(x,y) i + Q(x,y) j in the xy-plane with the property that at any point (a,b) # (0,0), G is a vector of magnitude var + b tangent to the circle x + y" = a + band pointing in the clockwise direction. (The field is undefined at (0,0).) b. How is G related to the spin field F shown on the right? A "spin" field of rotating unit vectors in the plane. a. G = ()i+ 0)