You are 40 years old and want to retire at age 60. Each year, starting one year from now, you will deposit an equal amount into a savings account that pays 7% interest. The last deposit will be on your 60th birthday. On your 60th birthday you will switch the accumulated savings into a safer bank account that pays only 3.5% interest. You will withdraw your annual income of $120,000 at the end of that year (on your 61st birthday) and each subsequent year until your 90th birthday. On that birthday you want to give$550,000 to your children. How much do you have to save each year to make this retirement plan happen?