6) The Johnsons want to be able to live off their retirement account for the next 20 years. They estimate they will need $4300 every other month to cover their expenses. They can open such an account that is compounded every-other-month, at 5.49%. How much should they deposit today, so that they are able to live comfortably for the next 20- years, assuming no other income

Please break down the question and explain each component of the formula and how you got there. Thanks!