A Pew Research Survey asked adults in the United States which technologies would be “very hard” to give up. The following responses were obtained: Internet 53%, smartphone 49%, email 36%, and land line phone 28% (USA Today website).

a. If 20 adult Internet users are surveyed, what is the probability that 3 users will report that it would be very hard to give it up?

b. If 20 adults who own a land-line phone are surveyed, what is the probability that 5 or fewer will report that it would be very hard to give it up?

c. If 2000 owners of smartphones were surveyed, what is the expected number that will report that it would be very hard to give it up?

d. If 2000 users of email were surveyed, what is expected number that will report that it would be very hard to give it up? What is the variance and standard deviation?