please explain!!

Marek plans to deposit $100 at the end of every 3 months for 10 years into a savings account which earns interest at 8% compounded quarterly. After the last deposit he intends to use the amount accumulated in the last 10 years as a withdrawal stream whereby he makes equal size withdrawals at the end of every 3 months for 15 years. If interest remains at 8% compounded quarterly what are the equal size withdrawals he will be able to collect at the end of every 3 months for 15 years?