On the first of january you place $100 into your bank account. on the first of each month after that you
deposit an additional $100. unfortunately, in the middle of the month you always withdraw 70% of your
money to pay bills.
a. how much money is in the account at the end of march?
b. how much money is in the account at the end of n months?
c. according to your rule, when will you have a balance of zero?