A Local Courier Service Advertises That Its Average Delivery Time

Multiple Choice

A local courier service advertises that its average delivery time is less than 6 hours for local deliveries.When testing the two hypotheses,H_o:μ ≥ 6 and H_A:μ < 6,μ stand for _____________.

A) the mean delivery time
B) the standard deviation of the delivery time
C) the number of deliveries that took less than 6 hours
D) the proportion of deliveries that took less than 6 hours