Part 1. http://www.wisc-online.com/Objects/ViewObject.aspx?ID=SCE304
https://www.wisc-online.com/learn/natural-science/earth-science/sce304/heat-transfer-conduction-convection-radiation
Part 3. http://www.lowes.com/cd_Understand+Heat+Transfer+and+Insulation_974680410_
Part 4. https://www.progress-energy.com/carolinas/home/save-energy-money/energy-saving-tips-calculators/100-tips.page?
https://www.wisc-online.com/learn/natural-science/earth-science/sce304/heat-transfer-conduction-convection-radiation
Part 3. http://www.lowes.com/cd_Understand+Heat+Transfer+and+Insulation_974680410_
Part 4. https://www.progress-energy.com/carolinas/home/save-energy-money/energy-saving-tips-calculators/100-tips.page?