Final answer:
The bottom half of the squama forms the walls of the external acoustic meatus, which is part of the ear canal. It is located in front of the petromastoid portion of the temporal bone.
Step-by-step explanation:
The question is asking about the anatomical location and function of the bottom half of the squama, which forms the walls of the external acoustic meatus. The external acoustic meatus is the part of the ear canal that leads from the outside of the head to the middle ear. It is located in front of the petromastoid portion of the temporal bone.