$4$s$\mathrm{.}4$ A couple wants to save for their daughter's college expense. The daughter will enter college eight years from now, and she will need $$50,000,$ $$51,000,$ $$52,000,$ and $$53,000$ in actual dollars over four school years. Assume that these college payments will be made at the beginning of each school year. The future general inflation rate is estimated to be $7\%$ per year, and the annual inflation$-$free interest rate is $6\%.$ What is the equal amount, in actual dollars, the couple must save each year until their daughter goes to college $?($a$)$ $$21,838($b$)$ $$21,945($c$)$ $$22,323($d$)$ $$22,53$

Explain using cash flow chart