ISC 2. Line integral practice. (30 points) Compute the line integrals F - dr of the following vector fields F over the corresponding paths C: (a) F= r, along the straight line C defined by r(t) = t, y(t) = 3t -1, z(t) = 2t, from the points (1, 2, 2) to (3, 8, 6). (b) F = (2ry, 2',3), along the path C which is the intersection of the paraboloid = = 12 +y- with the plane y = 2x, from (0, 0, 0) to (2, 4, 20). (c) F = (-y, x,0) counterclockwise along the circle C defined by a + y? = 4 from (2, 0) to (-2, 0). Hint: choose a good coordinate system