Eco-cool air conditioners cost $3000 to purchase, result in electricity bills of $1500 per year, and last for 5 years. Luxury Air models cost $5200, result in electricity bills of $1000 per year, and last for 8 years. The discount rate is 15% per year. Which model is more cost effective? (**please provide working)

5 6 Discount rate 15% 7 8 Cost Annual electricity bill Life (years) 9 Eco-cool air conditioners $3,000 $1,500 5 10 Luxury Air models $5,200 $1,000 11