4. If x is a critical value then f' (x) = 0. a. Always True b. Sometimes True c. Never True 5. If lim f (x) = 4, then... X-+00 a. f(x) has a vertical asymptote at 4. b. f' (x ) = 4. c. f (x) has a horizontal asymptote at 4. d. f (x) is increasing as x goes to infinity