Jоhn hаs just stаrted wоrking аnd he is gоing to save $2500 a year for the first 4 years.Then he hopes to get promoted and save a reasonable amount every year for the next 15 years. These are his prime working years.After that he will begin to wind down and save $4000 for the next 5 years and finally $1200 for the next 3 years after which he will retire.He wants to retire and spend $60,000 per year for as long as he needs (perpetuity).The rate is assumed to be 4% throughout. How much should he save during his prime working years?