anatomy and physiology questions?

1.)how is a strong nerve stimulus coded for by action potentials if all action potentials are identical?

2.) cancer is a genetic problem in which genes that control mitosis have been mutated. as a result, the cancerous cell will divide uncontrollably. many cell types develop cancer but neurons do not, the reason is........

3.)which of the following is false?

a.) the epidural space contains cerebrospinal fluid
b.) the subarachnoid space contains fat
c.) the dura mater is the thickest outer meninge
d.) the subdural space contains blood

4.) how is equilibrium controlled in humans??