A professor who hates being scheduled for 8 A.M. classes, or classes on Friday afternoons after 3 P.M., has decided to investigate whether student grades are affected by the time at which classes take place. She keeps track of the grades of students who are scheduled for class at 8 A.M. on Thursdays, 4 P.M. on Fridays, and 2 P.M. on Wednesdays. The marks of these classes are not, strictly speaking, random samples. However, if we consider the population as the marks of all students who attend the professor's classes over her entire career, we could think of particular classes as random samples. Check whether the conditions for ANOVA are met. If they are, con duct a test of hypothesis at the 1% level to see if it appears that the scheduled time for classes affects the marks. Explain why you should be cautious in interpreting these results.