A rechargeable battery is plugged into a charger. The graph shows C(t), the percentage of full capacity that the battery reaches as a function of time t elapsed (in hours). C percentage of full charge 100- 80 60 40 20 t 2 4 6 8 10 12 (hours) (a) What is the meaning of the derivative C'(t)? OC'(t) is the total percentage of full capacity with respect to elapsed time in hours. O C'(t) is the average rate of change of percentage of full capacity with respect to elapsed time in hours. OC'(t) is the instantaneous rate of change of percentage of full capacity with respect to elapsed time in hours. OC'(t) is elapsed time in hours required for a given percentage of full capacity to be reached. (b) Sketch the graph of C'(t). C C'