2. A tutor wants to know which night each week his students prefer to work on their assignments. Suppose a random sample of 49 students were asked on which night of the week they prefer to work on their assignment. Below is the summary table of the finding. Night Sun Mon Tue Wed Thu Fri Sat Number of 11 6 8 5 9 5 5 students (a) Calculate the expected frequency for each night. (5) (b) Test whether the frequencies are equally distributed during the week using a 5% level of significance. ( 15 )