1.-What is the size of 60 monthly payments and 5 annuities that result from the purchase of land with a value of $ 500,000, if the interest rate is 18% per year, and the payment conditions are 10%...

1.-What is the size of 60 monthly payments and 5 annuities that result from the purchase of land with a value of $ 500,000, if the interest rate is 18% per year, and the payment conditions are 10% down payment and the rest is distributed equally in monthly payments and annuities?

2.-A person deposits an annual amount in a savings account that decreases at a constant rate of $ 500 per year. The size of the first deposit made is $ 10,000 and the last one is $ 5,500. If 15% per year is earned in the savings account, how large must a constant annual deposit be for the same time, so that the accumulated amount is the same?