Question: The city council wants to conduct a survey to estimate the percentage of adults in that city who favor a gambling casino that city. They select a random sample of 300 phone numbers of households in the city, phone each these households between 6:30 p.m. and 9:00 p.m., and ask an adult in the household their opinion about a gambling casino, provided the phone is answered and an adult is available. If no one answers or an adult is not available, they phone that household a second time. What are the most likely potential source(s) of bias in this survey? Justify your answer(s).