Water is flowing continuously from a tap having an internal diameter `8xx10^-3m`. The water velocity as it leaves the tap is `0.4ms^-1`. The diameter of the water stream at a distance `2xx10^-1m` below the tap is close to:
A. `9.6xx10^(-3)m`
B. `3.6xx10^(-3)m`
C. `5.0xx10^(-3)`m
D. `7.5xx10^(-3)m`