Answer
a)Random.
b)Stratified.
c)Nominal.
d) Statistic.
e)Becomes a voluntary response sample.
Work Step by Step
a) Everyone in the population is equally likely to be selected, hence it is a random sample.
b)Randomly selecting people from the different states (each serves as a stratum) ensures us of getting a representative sample. Hence it is a stratified sample.
c) The responses are not numerical, hence we cannot rank them, hence it is nominal.
d)Data is coming from a sample, not from the population, hence it a statistic.
e) It would become a voluntary response sample, because people having a really strong opinion (either good or bad) are the most likely to answer, hence the results don't represent the general opinion correctly.