In the past, the mean running time for a certain type of flashlight battery has been 8.5 hours.
The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has changed as a result.
A)Lower-tailed
B)Upper-tailed
C)Two-sided

Question

Quizplus · Accepted Answer

The manufacturer is interested in determining whether the mean running time has changed in either direction (increase or decrease), which necessitates a two-sided hypothesis test.

In the Past, the Mean Running Time for a Certain