A city official has stated that 20% of the items sold by pawn shops within the city have been stolen. Ralph has just purchased 4 items from one of the city's pawn shops. Assuming that the official is correct, and for x = the number of Ralph's purchases that have been stolen, determine the following:
a. P(x = 0)
b. P(2 < x)
c. P (1 < x < 3)
d. P (x < 2)