Completing a two-way ANOVA table

In the following two-way ANOVA table the $F$ ratio corresponding to the block source of variation is $2.5$.

| Source | df | ss | |—|—|—| | Treat | 3 | 2.5 | | Block | 2 | $a$ | | Error | — | 9.0 | | Total | 11 | $b$ |

Hence $a$, the block sum of squares, and $b$, the total sum of squares, are: