intro.: 2x |-----------8-7-8-7-------------------------------------------- |-8---8--10----------10--8-7-8---8------------------------------------ |---7--------------------------7------------------------------ |------------------------------------------------------------- |------------------------------------------------------------- |------------------------------------------------------- 3x |---------8-7-8-7-------------------8-7-8-7----------------------- |---8--10----------10-8-7-8---8--10---------10--8-7-8-------------------- |-9-------------------------9------------------------------ |---------------------------------------------------------- |-------------------------------------------------------- |--------------------------------------------------------