A 2015 study conducted by the National Center for Health Statistics (www.cdc.gov/nchs/data/ nhis/earlyrelease/wireless201512.pdf) found that 51% of U.S. households had no landline service. This raises concerns about the accuracy of certain surveys, as they depend on random-digit dialing to households via landlines. We are going to pick five U.S. households at random:
a) What is the probability that all five of them have a landline?
b) What is the probability that at least one of them does not have a landline?
c) What is the probability thc)at at least one of them does have a landline?