I have seen the question below on this site but the answer does not include the depth I need to understand how the answer is found. Can someone walk through this and explain the values used for the financial calculator?

Ms. B is 55 years old and is planning to retire at age 62. She wants to have a retirement income from that point until age 85. She projects that she will need $5,000 per year during her retirement to supplement her other retirement income. In addition, she wants to leave an inheritance of $25,000 each to her four grandchildren. She has accumulated a nest egg $25,000 at this point. Assume that she can invest at a 9% annual rate in the pre-retirement period, that her funds can be invested at a 10% annual rate after retirement, and that contributions and withdrawals occur at the end of each year. If you use a financial calculator to solve, show all keystrokes and values input (e.g. FV = $XXX, PMT = $YYY, etc.) a. Sketch the time line of the cash flows for this problem. b. Does she have enough accumulated at this point to fund her plan? c. If she does not have enough, how much must she save each year for the next 7 years in order to fund her plan?