Answer:
a. Expected frequency of losses per semester = 0*0.08 + 5*0.16 + 10*0.28 + 15*0.32 + 20*0.14 + 25*0.02
Expected frequency of losses per semester = 11.7 losses per semester
b. Variance = (0-11.7)²*0.08 + (5-11.7)²*016 + (10-11.7)²*0.28 + (15-11.7)²*0.32 + (20-11.7)²*0.14 + (15-11.7)²*0.02
Variance = 10.9512 + 7.1824 + 0.8092 + 3.7848 + 9.6446 + 3.5378
Variance = 35.61
c. As losses equal $60, expected losses per semester = 11.7*$60 = $702
d. Expected losses of all textbooks per semester = 250*11.7*$60 = $175,500