C[C@H](CCC(=O)O)[C@H]1CC[C@@H]2[C@H]3CC[C@H]4C[C@H](O)CC[C@@]4(C)[C@@H]3CC[C@@]21C
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. How many bonds in the molecule are rotatable?