Aditya deposits $500 in a savings account over the course of a year. he deposits money into the account throughout the next year until his balance is quadrupled. the next year he does the same and deposits money into the account until his previous year’s balance is quadrupled. assume that this trend continues and his account does not earn interest. consider his initial balance to be year one. what explicit formula can be used to determine the balance of his savings account at the end of n years?
a) an=4⋅500^n
b) an=500⋅4^n−1
c) an=500⋅4^n
d) an=4⋅500^n−1