In an African wildlife reserve your jeep is travelling at a constant speed of 105 km/hr alongside a cheetah running at full speed. The animal, frightened by the jeep's noise, keeps at a constant distance of 60 m from the vehicle. Not having paid much attention to the surrounding landscape, you suddenly realize that your jeep is passing the very same spot where it was 60 seconds before. The speed of the cheetah is
(a) 105 km/hr.
(b) 94 km/hr.
(c) 99 km/hr.
(d) 82 km/hr.