A motorboat in still water travels at a speed of 36 km/hr. It goes 56 km upstream in 1 hour 45 minutes. The time taken by it to cover the same distance down the stream will be a. `1\ text(hour)\ 24\ text(minutes)` b. `2\ text(hour)\ 21\ text(minutes)` c. `2\ text(hour)\ 25\ text(minutes)` d. `3\ text(hours)`