Composition series of $D_{12}$ (of order $12$).

Question

I find that $$\{id,\langle r^2\rangle, \langle r\rangle,D_{12}\}$$ and $$\{id,\langle r^3\rangle, \langle r\rangle,D_{12}\}$$ are composition series.

Are there any more composition series of $D_{12}$?

What about Sylow $2$-subgroup - could be in composition series?