The top width and depth of flow ina rectangular channel were measured as 4m and 1m respectively. The measured velocities on the center line at the water surface, 0.2m and 0.8m below the surface are 0.7 $$\frac{m}{s}$$,0.8 $$\frac{m}{s}$$,0.6 $$\frac{m}{s}$$ respectively. Using two point method of velocity measurement, the discharge $$(in \frac{m^{3}}{s})$$ in a channel is

A

1.4

B

1.2

C

1.0

D

0.8