I really need help on this question it's from math 193.

A quadcopter is a small remote-controlled aircraft, sometimes called a "drone." Suppose that the height above the ground of a quadcopter in meters is given by s (t), where t measures the number of seconds since the quadcopter was launched. A graph of the function s is shown as follows. s(t) 6 A w N O 8 9 10 11 12 13 14 15 Let v(t) be the function that gives the vertical velocity of the quadcopter at time t. That is, v(t) measures the rate of change in height with respect to time in m/s. Part A: The value of v(t) will be positive when the quadcopter is rising. On what interval is v(t) > 0? Give your answer as an inequality, and approximate your answers to the nearest half-second. Hint The quadcopter is rising when's is increasing. Answer: Part B: The value of v(t) will be negative when the quadcopter is descending. On what interval is v(t)