An econometrics class has 80 students, and the mean student weight is 145 lb. A random sample of 4 students is selected from the class, and their average weight is calculated. Will the average weight...

An econometrics class has 80 students, and the mean student weight is
145 lb. A random sample of 4 students is selected from the class, and their
average weight is calculated. Will the average weight of the students in the
sample equal 145 lb? Why or why not? Use this example to explain why
the sample average, Y, is a random variable ?