Speed of train is constant in each minute.
It starts journey at 10 km/hr.
After every minute it increases its speed by 200%.
After end of 4th minute it reaches at its full speed and maintain it till the end of 22nd minute.
After which it keeps reducing its speed to 1/3 of its current speed for every minute till end of 25th minute at which its speed is reduced to 10 km/hr again.
What is distance between two stops (in km) ??