water in a canal,30dm wide and 12 dm deep is flowing with velocity of 10 kmph.?

Question

how area will it irrigate in 30 min., if 8 cm standing water is required for irrigation ?

Answer 1

0.08A = (30/60)(1000)(0.30)(0.12), m^3
A = 225 m^2, the area ithe canal will irrigate in 30 min.
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Pay attention to the units.