Van Farms INC, is a small grower of watermelons.Van Farms estimates that watermelon output would increase by 1200 per month with an additional 1000 gallons water/month .Alternatively, watermelon output could be increased by 500/month with an additional 2 tons of fertilizer/month. assuming the cost of water is $0.03/gallon and the fertilizer is $25/ton, is Van Farms using an optimal combination of fertilizer and water? why or why not?