A rabbit runs in a straight line with a velocity of +1.7 m/s for a period of time, rests for 12 s, and then runs again along the same line at +0.63 m/s for an unknown amount of time. The rabbit travels a total distance of 1080 m, and its average speed is 0.87 m/s.
(a) What is the total time the rabbit spends running at 1.7 m/s?
(b) How long does it spend running at 0.63 m/s?