Your grandfather is 82 years old. Over the years, he has accumulated savings, and currently, their amount is $80,000. He thinks he will live another 10 years and intends to spend the savings until then. Today, he deposits his money in a bank deposit, bringing him a return of 12% per year, the deposit can be arranged so that he withdraws all his funds in equal monthly installments. The first withdrawal starts after one month has passed from now.

a) How much $ per month will he be able to withdraw?

b) Calculate the effective annual rate that he receives, bearing in mind that the bank calculates and capitalizes the received income on a monthly basis.