4. Consider the function f(x) = x23x. The first derivative of this function is f' (x) = x(2 + 3x)e3x. (a) (5 points) What are the critical points of f (x)? (State the x -values.) (b) (4 points) On what interval is f(x) increasing and on what intervals is f (x) decreasing? Increasing: Decreasing: 5. (10 points) Water is being drained out of a cylindrical glass with radius 2 inches and height 4 inches. How fast is the height of the liquid changing if the volume decreases at a rate of 2nt te. Hint: The formula for the volume of a cylinder is V = arzh