Cc1cc(C)c(C)c(C(=O)C2OC(=O)C(C)(C)C(=O)C2(C)C)c1C
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. Amide C-N bonds are not counted because of their high barrier to rotation.  How many rotatable bonds does the molecule have?