What is the functional advantage of having air spaces in skull bones? what is the disadvantage to having these spaces lined with mucous membrane?

answer:

i believe the answer is d).

explanation:

i think this is because you are tearing apart the muscle, and then when you eat, the muscle re-heals, making itself even stronger.

edit: i put b) before but i meant to put d). sorry for the incorrect answer.

answer: depends on how munch your body can take ( personal advice use 6 lines then quit)

explanation:

answer:

It is true because...

Explanation:

but black guys,girls tend to have better voices than most people