(Annuity number of periods) Alex Karev has taken out a $180,000 loan with an annual rate of 12 percent compounded monthly to pay off hospital bills from his wife Izzy's illness. If the most Alex can afford to pay is $3,500 per month, how long will it take to pay off the loan? How long will it take for him to pay off the loan if he can pay $4,000 per month? Use five decimal places for the monthly percentage rate in your calculations