A year$$ ago, an investor bought $600$ shares of a mutual fund at $$$$7\mathrm{.}65$ per share. This$$ year, the fund has paid dividends of $$0\mathrm{.}72$ per share and had a capital gains distribution of $$$$0\mathrm{.}53$ per share.

a$.$ Find the$$ investor's holding period$$ return, given that this$$ no$-$load fund now has a net asset value of $$$$8\mathrm{.}21.$

b$.$ Find the holding period$$ return, assuming all the dividends and capital gains distributions are reinvested into additional shares of the fund at an average price of $$$ $7\mathrm{.}94$ per share.