Define: voluntary response a) population is divided into similar groups and a SRS is chosen from each group. b) the explanatory
variable(s) in an experiment. c) people who choose themselves for a sample by responding to a general appeal. d) choosing the individuals easiest to reach. e) directly holding extraneous factors constant. f) gives each member of the population a known chance to be selected. g) using extraneous factors to create similar groups. h) successively smaller groups are selected within the population in stages. i) every possible sample of a given size has the same chance to be selected.
