5. Show that c(t) = (t-3, et, t-1) is the flow line of the vector field F(x, y, z) = (-324, y, -2 2). 6. a) First sketch the flow line of the vector field T. U(x, y) = , (z, y) + (0, 0), 2 + yz r2 + 72 and b) then solve the flow line equation to find the flow line. 7. a) For a o E C'(R?), define the vector field U(x, y) = (-dy, or). Show that div U = 0; b) Given V(x, y) = (y, x), verify that divV = 0 and find a potential function v c C'(R? ) such that V = (-vy, (z)