Answer
a) Not independent
b) Independent
c) Not independent
d) Independent
e) Independent
Work Step by Step
a) The two samples consist of paired observations (two observations per person that are spread over the two samples), hence they are not independent.
b) Nobody can be in both samples and the samples were randomly selected, hence they are independent.
c) The two samples consist of paired observations (two observations per person which are spread over the two samples), hence they are not independent.
d) Nobody can be in both samples and the samples were randomly selected, hence they are independent.
e) Nobody can be in both samples and the samples were randomly selected, hence they are independent.