Assume the house has some insulation (can tolerate 22+3 .C, has single-layered glass window ) for N values 0-4; and good insulation (can tolerate 22#N*0.5 -C has single layered glass window) for N values 5-9. Air conditioner (A/C) runs when temperature is above or below the tolerable temperature. Use typical monthly temperature as shown in Figure 1. A/C only works when all the people are in the home, i.e from 6 PM to 12 AM on weekdays and anytime between 6 AM and 12 AM during weekends depending on the temperature. Assume monthly average high temperature (Tmax, average)+(15+N*2)% of Tmax average is valid for day time temperature for the month and 1%*(monthly average high + monthly average low) is valid between 6 PM and 12 AM. A/C consumes 2500 +200*N W when it runs. Chose appropriate approximations and calculation procedure as needed