Estimate the heating and cooling energy and cost savings incurred by converting a 20,000-cfm single duct reheat system to a VAV system in an office building located in Chicago, Illinois. For the CV system, the return air is measured to be 76°F and the cold duct air temperature is set to be 58°F. The HVAC system is operated 80 hours per week. For the analysis, consider only the sensible loads. The cost of fuel is $5/MMBtu and the boiler efficiency is 80 percent. The cost of electricity is $0.05/kWh and the chiller efficiency is 0.9 kW/ton. For Chicago, the number of weeks is 30 for the heating season (winter) and 21 for the cooling season (summer).