A can do $$\frac{1}{5}$$ of the work in 3 days and B can do $$\frac{1}{4}$$ of the work in 7.5 days. Working together, A and B can do $$\frac{4}{5}$$ of the same work in:

A

9 days

B

10 days

C

8 days

D

12 days