Which of the following statements about the speed of impulse conduction in a neuron is true?

Which of the following statements about the speed of impulse conduction in a neuron is true?
  a. Longer axons can transmit impulses faster than shorter ones.
  b. Unmyelinated axons transmit impulses faster than myelinated ones.
  c. Shorter axons can transmit impulses faster than longer ones.
  d. Nerve impulses travel faster than the speed of light.
  e. Unmyelinated axons with larger diameters transmit impulses faster than ones with small
  diameters

Question 2

Since all action potentials are identical, the intensity of a sensation depends on:
  a. whether a myelinated or unmyelinated neuron has been stimulated.
  b. the duration of the stimulation.
  c. whether the neuron stimulated is a pre- or postsynaptic neuron.
  d. the total number of neurons stimulated and the frequency of their discharge.
  e. the presence of an EPSP or IPSP, which allows for a graded response