PhysioEX 9.0 exercise 3 activity 9

I would say your answer is correct based on the activity data. Nice work 

Regardless of the type of neuron the typical resting membrane potential is the same value.

I am in need of some help with the following questions: (Exercise 3: Neurophysiology of Nerve Impulses Activity 6, 7, 8, and 9).

Activity 6,
      Question 1: Why are multiple action potentials generated in response to a long stimulus that is above threshold?
      Question 2: Why does the frequency of action potentials increase when the stimulus intensity increases?
      Question 3: How does threshold change during the relative refractory period?
      Question 4: What is the relationship between the interspike interval and the frequency of action potentials?

Activity 7,
      Question 1: How did the conduction velocity in the B fiber compare with that in the A fiber?
      Question 2: How did the conduction velocity in the C fiber compare with that in the B fiber?
      Question 3: What is the effect of axon diameter on conduction velocity?
      Question 4: What is the effect of the amount of myelination on conduction velocity?
      Question 5: Why did the time between the stimulation and the action potential at R1 differ for each axon?
      Question 6: Why did you need to change the timescale on the oscilloscope for each axon?

Activity 8,
      Question 1: When the stimulus intensity is increased, what changes: the number of synaptic vesicles released or the amount of neurotransmitter per vesicle?
      Question 2: What happened to the amount of neurotransmitter release when you switched from the control extracellular fluid to the extracellular fluid with no Ca2+?
      Question 3: What happened to the amount of neurotransmitter release when you switched from the extracellular fluid with no Ca2+ to the extracellular fluid with low Ca2+?
      Question 4: How did neurotransmitter release in the Mg2+ extracellular fluid compare to that in the control extracellular fluid?
      Question 5: How does Mg2+ block the effect of extracellular calcium on neurotransmitter release?

Activity 9,
      Question 1: Why is the resting membrane potential the same value in both the sensory neuron and the interneuron?
      Question 2: Describe what happened when you applied a very weak stimulus to the sensory receptor?
      Question 3: Describe what happened when you applied a moderate stimulus was to the sensory receptor?
      Question 4: Identify the type of membrane potential (graded receptor potential or action potential) that occurred at R1, R2, R3, and R4 when you applied a moderate stimulus?
      Question 5: Describe what happened when you applied a strong stimulus to the sensory receptor?