Use the Following to Answer the Questions Below

Essay

Use the following to answer the questions below:
A professor with a large introductory statistics class noticed that nearly half of his students missed class the day before a long break (like Thanksgiving Break or Spring Break). He randomly called on students and found 10 students in attendance and 10 students who had skipped class. Later in his office, he examined the current course grades for the 20 students he had selected. A plot of his findings and summary statistics are provided. Note that the grades were entered as proportions, and thus a grade of 0.925 is a 92.5% in the course.

-Verify that it is reasonable to use a t-distribution to construct a confidence interval, or perform a test about, the difference in mean grades for the two groups of students.