You invest $$6780$ in a floating rate guaranteed investment certificate. For the first $30$ months you earn $4\mathrm{.}9\%$ compounded semi$-$annually. For the next $8$ months you earn $4\mathrm{.}32\%$ compounded monthly. What is the maturity value of the certificate?

a

$$7775\mathrm{.}44$

b

$$7785\mathrm{.}44$

c

$$7857\mathrm{.}44$

d

$$7875\mathrm{.}44$

e

$$7888\mathrm{.}44$