Laying fiber-optic cable is expensive. cable companies want to make sure that if they extend their lines out to less dense suburban or rural areas, there will be sufficient demand and the work will be cost-effective. they decide to conduct a survey to determine the proportion of households in rural subdivision that would buy the service. they select a simple random sample of 5 blocks in the subdivision and survey each family that lives on one of those blocks. what is the name for this kind of sampling method?