Comerica Bank publishes information on new car prices in Comerica Auto Affordability Index. In the year 2007, Americans spent an average of $28,200 for a new car (light vehicle). Assume a standard deviation of $10,200.
a. Identify the population and variable under consideration.
b. For samples of 50 new car sales in 2007, determine the mean and standard deviation of all possible sample mean prices.
c. Repeat part (b) for samples of size 100.
d. For samples of size 1000, answer the following question without doing any computations: Will the standard deviation of all possible sample mean prices be larger than, smaller than, or the same as that in part (c)? Explain your answer.