4. (a) Evaluate feeds where C is the are of the parabola y = r² from (0,0) to (1,1) (b) Evaluate fyz cos x ds where C is given by x = t, y = 3 cost, z = 3 sint, 0 tπ. (c) Evaluate foxy dx + y² dy+yz dz where C is the line segment from (1,0, -1) to (3, 4, 2). 5. Determine if the following vector fields are conservative or not. If it is conservative, find the potential function f such that Vf = F