Jason has two retirement objectives. He wants to retire in 30 years. After retirement, he wants monthly

Question:

Jason has two retirement objectives. He wants to retire in 30 years. After retirement, he wants monthly retirement income of $20,000 per month for 20 years and leaves an inheritance of $1,000,000 for his son. If he can earn 11% until retirement and 8% after retirement, how much should he save per month until he retires?