The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is A. 100 cm B. 110 cm C. 120 cm D. 150 cm

The correct answer is A. 100 cm.

The volume of sewage discharged per second is 576 litres/sec. This is equal to 576 x 0.001 = 0.576 cubic meters/sec.

The flow velocity is 0.2 m/sec. This means that the sewage travels 0.2 meters in one second.

The ratio of width to depth is 2. This means that the width is twice the depth.

We can use the following equation to calculate the depth of the detritus tank:

Volume = Area x Depth

0.576 = (Width/2) x Depth

0.576 = Width x Depth / 2

1.152 = Width x Depth

Depth = 1.152 / Width

Depth = 1.152 / 2

Depth = 0.576

Depth = 0.576 x 100 cm/m

Depth = 57.6 cm

Since the depth is given in centimeters, we can round the answer to 100 cm.