i need help with questions 19-33

Use a graphing calculator to graph each function and to determine and classify its extrema. 19. f(x) = -4+3x -x2 20. V(w) = w3 - 7w - 6 21. g(x) = 6x3 + x2 - 5x - 2 22. h(x) = x4 - 4x2 - 2 23. f(x) =2x5 + 4x2 - 2x -3 24. D(t) = 13 + t 25. Determine and classify the extrema of f(x) = x4 + 5x3 + 3x2 - 4x. Determine whether the given critical point is the location of a maximum, a minimum, or a point of inflection. 26. y = x3, x = 0 27. y = -x2 + 8x - 10, x = 4 28. y = 2x2 + 10x - 7, x = -2.5 29. y = x4 - 2x2 + 7, x =0 30 . y = -x4 - 2x2, x = 2 31. y = x3 - 9x2 + 27x - 27, x =3 32. y = 2x3 + 7x2 - 2x + 1, x = -2 33. y = x3 - x2 + 3, x =