1. **Problem Statement:** The first question asks for the assumptions and requirements to use an independent t-test. 2. **Formula and Explanation:** The independent t-test compares the means of two independent groups to see if there is a statistically significant difference between them. 3. **Assumptions for Independent t-test:** - The two samples are independent of each other. - The data in each group are approximately normally distributed. - The variances of the two groups are equal (homogeneity of variance). - The data are measured at least at the interval level. 4. **Details:** - Independence means the samples do not influence each other. - Normality can be checked with tests like Shapiro-Wilk or by visual inspection. - Homogeneity of variance can be tested with Levene's test. 5. **Summary:** To use an independent t-test, ensure two independent samples, normal distribution, equal variances, and interval or ratio data.