Suppose you are conducting a study about how the average US worker spends time over the course of a workday. You are interested in how much time workers spend per day on personal calls, emails, and social networking websites, as well as how much time they spend socializing with coworkers versus actually working.

The most recent census provides data for the entire population of US workers on variables such as travel time to work, time spent at work, and break time at work. The census, however, does not include data on the variables you are interested in, so you obtain a random sample of 45 full-time workers in the United States and ask about personal calls, emails, and so forth. You are curious about how your sample compares with the census, so you also ask the workers the same questions about work that are asked in the census.

Suppose the mean break time per day from the most recent census is 36.8 minutes, with a standard deviation of 21.6 minutes. Your sample of 45 US workers provides a mean break time per day of 45.8 minutes with a sample standard deviation of 19.2 minutes.

Identify the following:

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