Please answer all 3

1. Which of the following is an example of a categorical variable? Select all that apply. (Select all that apply.) the proportion of backpacks that weigh more than 50 pounds the weight of a backpack the type of backpack used the number of books in a backpack 2. All the residents of a building were polled about whom they would vote for in the upcoming city election for mayor. What are the sample and population in this poll? 0 The population is the registered voters in the city; the sample is the residents of the building. Q The population is the registered voters in the city; the sample is a random sample of the residents in the building. 0 The population is the residents of building; the sample is the registered voters in the city. 0 The population is the residents of the building; the sample is the residents who responded. 3. A census reports that the mean retirement age is 68.3 years. In a random sample, the mean retirement age is 65.8 years. What does the mean of 65.8 years represent? O a statistic O a parameter Q a variable O a sample