Which best describes an axon with myelin and an axon without myelin?

Ecologist have observed a sharp increase of sulfur dioxide in the air . what might be a possible consequence of excessive sulfur dioxide in the air ? a. acid rain b. ozone layer depletion c. ozone layer hole d. increase in sea levels

Which of the following describes a boom period? a. as one population increases, another population decreases. b. as one population increases, the other population also increases. c. as one population decreases, another population increases. d. as one population decreases, another population also decreases

What is the difference between a scientific hypotheses and a scientific theory?