Statistics 1 for psych majors: null hypothesis, comparison distribution

 You determine the characteristics of the comparison distribution to answer which of the following questions?

a. Given a particular sample value, what is the probability of obtaining it if the research hypothesis is true?

b. Given a particular population value, what is the probability of obtaining it if the null hypothesis is false?

c. Given a particular sample value, what is the probability of obtaining it if the null hypothesis is true?

d. Given a particular population value, what is the probability of obtaining it if the research hypothesis is true?

I have no clue, would appreciate any help.