To evaluate the time of solving a test, 5 different types of tests were compared (A, B, C, D, E, ). 6 students were randomly selected to control for possible variance due to student taking the test and were treated as blocks in this experiment. The following values were obtained using the ANOVA procedure: SKT=250, SKTR=75, SKBL=56, =0.05. a) Test whether there are significant differences in the test solution time depending on the test type (Fk=2.87). b) Do you think that treating students as a block is important in this case? Explain (Fk=2.75). c) Compare the average times of solving test A and B by using the procedure of multiple comparisons NVR if solving test A a student needs 60 minutes on average and solving test B takes 67 minutes on average (tk=2.8).