The Cost and Demand Conditions for Residential Water Consumption Are

The cost and demand conditions for residential water consumption are shown below.If there are 450,000 residential water customers,then develop an optimal two-part pricing scheme and answer the question. At the optimal user fee,the water utility company will lose _______ per month.

A) $0
B) $1,440,000
C) $1,680,000
D) $2,400,000
E) $3,242,500