DETERMINE THE TYPE OF BIAS: 1.a) The village of Oak Lawn wishes to conduct a study regarding the income level of households within the village. The village manager selects 10 homes in the southwest corner of the village and send an interviewer to the homes to determine household income. 1.b) Cold Stone Creamery is considering opening a new store in O'Fallone. Before opening, the company wants to know the percentage of households in O'Fallone, that regularly visit an ice cream shop. The market researcher obtains a list of households in O'Fallone, randomly selects 150, and mails a questionnaire that asks about ice cream eating habits and flavor preferences. Of the 150 questionnaires mailed, 43 are returned. I 1.c) To determine the public's opinion of the police department, the police chief obtains a cluster sample of 15 census tracts within his jurisdiction and samples all households in the randomly selected tracts. Uniformed police officers go door to door to conduct the survey.