Which of the following statements are TRUE of the axial skeleton?  (there may be more than one answer)

1. The rib cage is pulled down and out to bring about inhalation
2. The largest vertebrae are the cervical vertebrae that support the head
3. The pituitary gland is located in a depression called "sella turcica" in the frontal bone
4. The paranasal sinuses make the skull lighter in weight
5. The vertebral canal contains the meninges and spinal cord
6. The ear canal is a tunnel into the parietal bone
7. The rib cage protects the liver and the lungs from mechanical injury
8. The parts of the sternum are the manubrium, body, and xylophone process
9. The eyes are protected by the bony sockets called orbits
10. The spinal cord enters the skull through the foramen magnum in the sphenoid bone  
11. The rib cage has eight pairs of true ribs
12. The nasal bones form the nasal septum

An antagonist to a muscle that flexes the arm would be a muscle that: 

1. Adducts the arm
2. Abducts the arm
3. Extends the arm
4. Rotates the arm