(a) A city manager wants to poll residents about a park renovation. Which of the following best describes a cluster sample of residents?The city manager forms groups of 12 residents based on the streets the residents live on. Then, she selects all of the residents in 5 randomly chosen groups.The city manager uses a computer program to draw 60 residents at random and selects these residents. Every set of 60 residents is equally likely to be drawn by the computer program.The first 60 residents who walk into city hall one day are easily accessible. So, the city manager selects these residents.(b) A manager at a bus company wants to survey employees about the new uniforms. Which of the following best describes a systematic sample of employees?The manager forms groups of 8 employees based on the departments the employees are in. Then, she selects all of the employees in 7 randomly chosen groups.The manager forms 7 groups of employees based on the departments the employees are in. Then, she selects 8 employees at random from each group.The manager takes a list of the employees and selects every 7th employee until 56 employees are selected.(c) A consultant wants to ask workers at a factory about the workers' job satisfaction. Which of the following best describes a convenience sample of workers?All of the workers on the second floor of the factory building are easily accessible. So, the consultant selects the first 72 workers from the second floor to arrive at work on a particular day.The consultant takes a list of the workers and selects every 3rd worker until 72 workers are selected.The consultant assigns each worker a different number. Using a random number table, he draws 72 of those numbers at random. Then, the consultant selects the workers assigned to the drawn numbers. Every set of 72 workers is equally likely to be drawn using the random number table.