A proposal has been made for improving the downtown area of a small town. The plan calls for PROBLEMS $519$ banning vehicular traffic on the main Street and turning this street into a pedestrian mall with tree plantings and other beautification features. This plan will involve actual costs of $$7,500,000$ and, according to its proponents, the plan will produce benefits and disbenefits to the town as follows:

Benefits:

$$ Increased sales tax revenue $$475,000$ per year

$$ Increased real estate property taxes $$300,000$ per year

$$ Benefits due to decreased air pollution $$80,000$ per year

$$ Quality of life improvements to use $$75,000$ per year Disbenefits:

$$ Increased maintenance $$225,000$ per year

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$($a$)$ Compute the B$$C ratio of this plan based on a MARR of $10\%$ per year and an infinite life for the project.

$($b$)$ How does the B$$Cratio change for a $20-$yearproject life?

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