Hi there!
a. A stratified sample can be used by dividing the tenants into two groups: those who have children and those who do not have children. Then, a Sample Random Sample FROM EACH stratum can be conducted for a total of 16 tenants surveyed.
b. Using a cluster sample in this situation could introduce undercoverage or selection bias if there is a distinction between those on some floors and those on others. For example, tenants on lower floors might be more opposed to a playground (ex: noise, crowd, etc.) in comparison to those on higher floors.
