Rebecca invested $$1,500$ at the beginning of every $6$ months in an RRSP for $11$ years. For the first $8$ years it earned interest at a rate of $3\mathrm{.}90\%$ compounded semi$-$annually and for the next $3$ years it earned interest at a rate of $5\mathrm{.}70\%$ compounded semi$-$annually.

a$.$ Calculate the accumulated value of his investment at the end of the first $8$ years.

$$43,274\mathrm{.}56$

$$43,550\mathrm{.}05$

$$27,850\mathrm{.}63$

$$28,393\mathrm{.}72$

b$.$ Calculate the accumulated value of her investment at the end of $11$ years.

$$43,274\mathrm{.}56$

$$43,550\mathrm{.}05$

$$38,335\mathrm{.}35$

$$28,393\mathrm{.}72$

c$.$ Calculate the amount of interest earned from the investment.

$$10,550\mathrm{.}05$

$$10,274\mathrm{.}56$

$$9,608\mathrm{.}42$

$$941\mathrm{.}63$