Salvatore will contribute $$500$ to a mutual fund at the beginning of each calendar quarter.

a$.$ What will be the value of his mutual fund after $61/2$ years if the fund earns $7\mathrm{.}6\%$ compounded annually? $($Do not round intermediate calculations and round your final answer to $2$ decimal places.$)$

Value of mutual fund $

b$.$ How much of this amount represents investment earnings? $($Do not round intermediate calculations and round your final answer to $2$ decimal places.$)$

Investment earnings $