I have a exam tomorrow but I need help for this question

a lean of 20.000 is to be amortised by equal payment of the end of each year for 4 years. İf interest is calculate at the save of %5 annualy

a) annual payment

b) the principal at the beginning of third year?

c) the total interst will be paid

d) Rest of the debt at the end of 2nd year

Need help and thank you