An experiment is conducted to estimate the difference in work productivity for employees under two conditions: with and without music playing in the background. Twenty employees volunteered to be part of the study. Ten of the volunteers were randomly assigned to work for one week with music playing in the background. The other 10 volunteers worked for one week without music playing in the background. Productivity is measured by counting the number of units produced for the week. A 99% confidence interval for the difference in the population means is (1.525, 7.275). What is the interpretation of this interval?

We can be 99% confident that between 1.525 and 7.275 additional employees were productive while working without music playing in the background versus working with music playing in the background.

We can be 99% confident that between 1.525 and 7.275 fewer employees were productive while working without music playing in the background versus working with music playing in the background.

We can be 99% confident that the true difference in the population mean number of units produced by all employees who work without listening to music for one week is about 1.525 to 7.275 units greater than the mean number of units produced by all employees who work while listening to music for one week.

We can be 99% confident that the difference in the mean number of units produced by the 10 employees who worked without listening to music for one week is about 1.525 to 7.275 units greater than the mean number of units produced by the 10 employees who worked while listening to music for one week.