'- Kelsha lives in a town of 3400 people. She works for the mayor's ofce and wants to see If there Is support for spending town funds on renovating the old theater. She takes out advertisements in the local newspaper and on the local TV news, asking town residents to meet at the park next Monday afternoon to discuss this question. Are you In favor of, or do you oppose, the town spending money to renovate the old theater? There were 64 residents who showed up at the park. Of these, 53 said they oppose spending money to renovate the old theater. (a) Identify and describe the most prominent source of bias in Keisha's study. Choose the best answer from the choices below. The bias comes from the phrasing of the question and the context in which it is asked. The responses are unlikely to be truthful. The bias comes from the sampling done in the study. Keisha only sampled from residents of the town, so the sample is a sample of convenience. The bias comes from the fact that the residents voluntarily chose to be in the sample by showing up to the park. Volunteers are likely to have characteristics that do not reect the population as a whole. The bias comes from having too many of the residents who showed up to the park who did not respond to the question. These residents might answer the question differently than those who did. There is no or very little bias in Keisha's study. The sample size is larger than 30, so it is large enough to eliminate any potential source of bias. (b) Describe something Keisha could have done to reduce the most prominent source of bias in the study. Choose the best answer from the choices below. Run follow-up advertisements reminding the towns residents to come to the park on Monday afternoon. That way the number of residents who do not respond would be decreased. Change the phrasing of the question and make sure that the residents who showed up to the park oould answer the question anonymously. That way the residents would be more likely to answer truthfully. Expand the study to Include all residents of the state. This way the sample is no longer a sample of convenience. Modify the study so that Keisha chooses the sample, ideally a random sample, of the residents who participate. That is, modify the study so that the residents do not voluntarily choose to be in the sample. As the sample size is sufciently larger the study has no or very little bias. So, there is nothing Keisha needed to have done to reduce bias