17. Use Stokes' Theorem to evaluate the line integral: oz'dx + xdy + 2zxdz C where C is the circle x2 + y2 = 1 in R' lying on the plane z = 1 with counterclockwise orientation. Hint: you can pick any surface with boundary C. May I suggest the upper half of the sphere x2 + y2 + (z - 1)? = 1 which has equation in cylindrical coordinates r2 + (z - 1)2 = 1 where 2 2 z 2 1