As part of a research project on college students' time, you want to evaluate the idea that college students should be thought of as part-time workers as well as students. Thus, you want to know whether or not it is accurate to describe college students as half-time workers, i.e., working 20 hours per week, or whether college students should be thought of as a distinct category of worker.

You sample 25 randomly selected UMN undergrads to learn how many hours per week they work during the academic year. You find a sample mean of 15 hours per week and a sample standard deviation of 12.5 hours.

1a. Write out null and alternative hypotheses for your significance test. Be sure to say which is which. You can answer either in English or in symbolic notation.

1b. Do the calculations necessary to evaluate these hypotheses using a t test at the 95% confidence level. Report your t value and your t* critical value.

1c. What do you conclude about your hypotheses? Why?