A river has a steady speed of 0.461 m/s. A student swims upstream a distance of 1.00 km and swims back to the starting point.
(a) If the student can swim at a speed of 1.29 m/s in still water, how long does the trip take?
(b) How much time is required in still water for the same length swim?
(c) Intuitively, why does the swim take longer when there is a current?