Calculate the net present value $($NPV$)$ over a $10-$year period for a $10,000$ square foot facility

when choosing between:

a$)$ Standard light fixtures costing $$15$ per square foot with a projected HVAC system size

requirement of $100$ tons.

b$)$ More expensive, energy$-$efficient light fixtures costing $$25$ per square foot that would allow for

a reduced HVAC system size requirement of $80$ tons.

The cost of the HVAC system is $$2,000$ per ton with an annual operation cost of $$1,500$ per ton of

HVAC capacity. Use a $5\%$ discount rate for the NPV calculation. Show all calculations and justify

your choice based on the NPV of initial and operational cost considerations.