Question

which of the following situations would be most appropriate for using a two - dependent - sample t - test?
measure participants blood pressure before and after a treatment
compare the number of hours worked by employees in two different departments
analyze the sales figures of two different stores
compare heights of students in two different schools

Explanation:

A two - dependent - sample t - test is used when we have two related samples. In the case of measuring participants' blood pressure before and after a treatment, the same participants are measured twice (before and after), so the samples are dependent.
For comparing the number of hours worked by employees in two different departments, the employees in one department are different from those in the other department (independent samples).
When analyzing the sales figures of two different stores, the stores are independent of each other (independent samples).
When comparing heights of students in two different schools, the students in one school are different from those in the other school (independent samples).

Answer:

Measure participants' blood pressure before and after a treatment.