Three groundwater well fields are being prospected for water supply to a nearby town and preliminary investigations have obtained the following net benefit functions for different levels of supply from the well fields. Well field 1: NB(x1) = 4x1 - 0.6x₁² Well field 2: NB(x2) = 5x2 - x^₂2 Well field 3: NB(x3) = 6x3 - 0.3x₃² m3/ Where xi is the annual water supply from well field i in 3million m³/ year and NB(xi) is the respective net benefit in millions of Rands.

i) What are the ideal supply levels from each well field?

ii) Using the steepest hill climbing approach, determine the supply from each well field that would m³ maximize net benefit for a supply of 12 million /year to the town. Apply an iteration step of 3million m³ /year in the analysis.