O=C(O)CCN1CC2([N+](=O)[O-])CC=C(OCCO)C([N+](=O)[O-])(C1)C2
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?