How big should the diameter of the pipeline be if 5600 m3 of water is to pass through it per hour?

How big should the diameter of the pipeline be if 5600 m3 of water is to pass through it per hour? The maximum permissible water outlet speed is 2.5 m / s.

The solution of the problem:
1. Let S be the required cross-sectional plane of the pipeline.
Then 5600 m3 / S = l – this is the distance the water must travel in the water supply system.
2.l / v = 1 hour;
l = v * 1 hour.
l = 2.5 m / s * 3600 s = 9000 m.
3. S = V / l;
S = 5600 m3 / 9000 m = 0.62 m2.
4. S = π * R & 2;
R2 = S / π;
R2 = 0.62 m2 / 3.14 = 0.197 m2;
R = 0.44 m.
5.d = 2 * R;
d = 0.44m * 2 = 0.88m ~ 0.9m ~ 90cm.
Answer: 90 cm.