Instruction 9-3 An Appliance Manufacturer Claims to Have Developed a Compact Microwave

Multiple Choice

Instruction 9-3
An appliance manufacturer claims to have developed a compact microwave oven that consumes a mean of no more than 250 W. From previous studies, it is believed that power consumption for microwave ovens is normally distributed with a population standard deviation of 15 W. A consumer group has decided to try to discover if the claim appears true. They take a sample of 20 microwave ovens and find that they consume a mean of 257.3 W.
-Referring to Instruction 9-3,the population of interest is

A) the power consumption in the 20 microwave ovens.
B) the mean power consumption in the 20 microwave ovens.
C) the mean power consumption in all such microwave ovens.
D) the power consumption in all such microwave ovens.