A boat which has a speed of `5kmh^(-1)` in still water crosses a river of width 1 km along the shortest possible path in 15 min. The velocity of the river water in `km h^(-1)` is

Options

A. Distance travelled by the particle is `212.5 m`
B. distance covered by the particle when moves with constant velocity is `100 m`
C. Velocity of the particle at `t=25s` is `5 m//sec`
D. Velocity of the particle at `t=9s` is `8 m//sec`

Answer

A, C, D

Explanation

Area of the curve gives distance.