Becky is 22 years old and just started a new job today. Her current plan is to work until age 62 and then retire and travel the world. Based on her family history and general health, she expects to live until 92 and then die on her birthday. She wants to be able to withdraw $20,000 on the FIRST day of each month during retirement and she expects to be able to earn 8% on her investments during her life. How much must she invest at the end of each month of her working life in order to fund her retirement?