A river has a steady speed of 0.250m/s. A student swims upstream a distance of 1.00 km and swims back to the starting point. If the student can swim at a speed of 1.00 m/s in still water, how long does the triptake (swimming up and down in the current)?
If the water were still, by how much would the trip be longer or shorter? (Give a negative answer for a shorter trip.)