1

1

1

1

2

�

2

�

�

2

2

�

�

�

6

6

6

6

6

6

6

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�

�