a) Find the values for t such that 0 < t2m where the parametric curve r=cost, y=cos 3t has a/some Horizontal tangent line(s). Show your work. (4 points) b) Find the point(s) (x, y) where the parametric curve x = t2-2t,y=t3-3t + 2t has a/some Vertical tangent line(s). Here we want you to find the coordinate of the point(s) and not just the value(s) for t. Show your work. (2 points)