9

The manager of an automobile dealership has introduced a new bonus plan designed to increase sales volume. Historically, the mean sales volume has been 14 automobiles per month. The manager wants to conduct a research study to see if there is evidence to conclude that the new bonus plan increases average sales volume.

What conclusion is appropriate when H₀ cannot be rejected?

When H₀ cannot be rejected, there [ Select ] ["is not", "is"] enough evidence to conclude that the mean sales volume has [ Select ] ["not changed", "increased", "changed", "not increased"] since implementation of the bonus.