Table $18-1$

Imagine a small town in which only two residents, Rochelle and Alec, own wells that produce safe drinking water. Each week Rochelle and Alec work together to decide how many gallons of water to pump. They bring the water to town and sell it at whatever price the market will bear. To keep things simple, suppose that Rochelle and Alec can pump as much water as they want without cost so that the marginal cost of water equals zero. The town's weekly demand schedule and total revenue schedule for water is shown in the following table:

$\backslash$table$[[\backslash$table$[[$Quantity$],[($Gallons$)]],\backslash$table$[[$Price$],[($Dollars per$],[$gallon$)]],\backslash$table$[[$Total Revenue and Total$],[$Profit$],[($Dollars$)]]],[0,60,0],[100,55,5,500],[200,50,10,000],[300,45,13,500],[400,40,16,000],[500,35,17,500],[600,30,18,000],[700,25,17,500],[800,20,16,000],[900,15,13,500],[1,000,10,10,000],[1,100,5,5,500],[1,200,0,0]]$

Refer to Table $18-1.$ If the market for water were perfectly competitive instead of monopolistic, how many gallons of water would be produced and sold?

a$.600$ gallons

b$.900$ gallons

c$.0$ gallons

d$.1,200$ gallons