3. A soil has a mass water content of 0.15 kg kg before receiving 90 mm of irrigation. Assume all the irrigation is retained in the upper 1 m and that the bulk density is 1250 kg m³. Assume pw = 998 kg m³. a) Calculate the volume of water (in litres) retained in the upper 1 m of soil over an area of 1.3 ha before the rain. [5] b) Calculate the equivalent depth of water after the irrigation.[2] T
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