8. (4 points) For February 23, the boy Zhenya was given a chocolate bar of size $3 \times 3$, on each piece of which a unique picture is drawn, with each picture appearing only once. In each move, Zhenya can bite off one piece that has no more than three common sides with other pieces that have not yet been eaten. In how many ways can Zhenya eat his chocolate bar?

Answer: $\frac{4}{5} \cdot 9!=290304$.