A conversion of land from tomato farming to cotton is planned. Is it true that less water will be used to supplement rainfall based on one growing season ? Explain and support your answers with calculations . If the land area is 40 hectare , what is the volume of the reservoir that should be built to hold enough water for one month to irrigate the cotton , consider precipitation zero and 160% of the water must be provided. ( Assume humid area with monthly daytime hour coefficient of 10 and mean annual temperature 65 F , and the month is 30 days )
(Crop) ( Lenght growing season) ( consumptive use coefficient)
* Tomatoes 4 months .65 - .7
* Cotton 7 months .6 - .7