Let f be a function define on the closed interval -5 ≤ x ≤ 5 with f(1) = 3. The graph of f', the derivative of f, consists of two line segments, as shown above. (a) For -5 < x < 5, find all values x at which f has a relative maximum. Justify your answer.

(b) For -5 < x < 5, find all values x at which f has a point of inflection. Justify your answer.

(c) Find all intervals on which the graph of f is both concave up and also has a positive slope. Explain your reasoning.

(d) Write the equation of the tangent line to f at x=1.

(c) Find f''(4.5)