Students are often asked to rate their professors' teaching, typically on a 1 to 5 scale: 1 being the lowest ranking and 5 being the highest. In an educational psychology class of 25 students, 3 gave their instructor a rating of 1, 4 students gave a rating of 2, 8 students gave a rating of 3, 7 students gave a rating of 4, and 3 students gave a rating of 5.

1. What are the mean and median ratings? [4]
2. What are the variance and standard deviation of the ratings? [6]
3. What might be a problem with computing the statistics in questions "a" and "b"? [4]
4. What are alternative descriptive statistics for the measures calculated in parts a and b of the question?[6]