Your family cabin now has a roof that is rectangular, 60 feet by 20 feet, and is covered by 2 inch thick hardwood siding and tapped wood shingles. You propose adding 2 inches of cellulose fiber insulation under the hardwood. You maintain the temperature inside the cabin at 70 degrees Fahrenheit and the outside temperature during the winter averages about 30 degrees. You heat the cabin with propane that has energy content of about 92,000 Btu per gallon and costs $1.60 per gallon. Calculate the difference in heat loss through the roof if you add the insulation compared to the current roof and calculate the potential monetary savings in one week from adding the insulation.