(a) A city manager wants to poll residents about a park renovation. Which of the following best describes a random sample of residents? O The first 72 residents who walk into city hall one day are easily accessible. So, the city manager selects these residents. O The city manager forms groups of 8 residents based on the streets the residents live on. Then, she selects all of the residents in 9 randomly chosen groups. O The city manager uses a computer program to draw 72 residents at random and selects these residents. Every set of 72 residents is equally likely to be drawn by the computer program. (b) A bank analyst wants to ask customers who have a mortgage with the bank about the customers' home-buying experiences. Which of the following best describes a stratified sample of customers? O The analyst forms groups of 9 customers based on the cities the customers live in. Then, she selects all of the customers in 6 randomly chosen groups. O The analyst forms 6 groups of customers based on the customers' mortgage amounts. Then, she selects 9 customers at random from each group. O The analyst uses a computer program to draw 54 customers at random and selects these customers. Every set of 54 customers is equally likely to be drawn by the computer program. (c) A host on a cruise ship wants to collect data on the time passengers spend at various activities on board. Which of the following best describes a convenience sample of passengers? The host takes a list of the passengers and selects every 5" passenger until 90 passengers are selected. The host forms 5 groups of passengers based on the levels of the ship that the passengers' cabins are on. Then, he selects 18 passengers at random from each group. O The host selects the first 90 passengers who board because these passengers are easily accessible. X 5