Fuel Consumption and Cars The Massachusetts State Police union is interested in the number of miles driven by each officer during an 8-hour shift. Twelve officers are selected from the 11:00 p.m. to 7:00 a.m. shift, and the number of miles traveled by each officer is recorded.
a. Is this an observational or an experimental study?
b. Describe the population and the sample in this problem.
c. Is this a random sample? Justify your answer.