4) Complete both parts

a) Solve the surface integral \iint_{S} x Z d S given that S is part of the plane z = 4 - 2x - 2y in the first octant. b) Evaluate the work integral \int_{C} \mathbf{F} \cdot d \mathbf{r} below given F = sin x i + cos y j + xz k where C is represented by the equation r(t) = t³ i − t² j + t k, t = [0,1].