Explanation:
after the first year its 10000÷100*8+10000=10800. after the second year its 10800÷100*8+10800=11664. after the third year its 11664÷100*8+11664=12597.12. and after the fourth year its 12597.12÷100*8+12597.12=13,604.8896$. If you want you can round it up to 13,605$