Person A completes a work $$W_1$$ in 6 hours while person B completes another work $$W_2$$ in 6 hours. If $$W_1$$ is only equal to two-thirds of $$W_2$$ then the number of hours required for A and B together to complete both $$W_1$$ and $$W_2$$ is:

A

6

B

7

C

5

D

8