1) According to a survey conducted 2015, the two most popular social networking sites in the United States are facebook and linkedin. Of all adult internet users, %69 have facebook acct, %25 have linkedin acct, and %19 visit both facebook and linkedin.
a) Find the probability that an adult internet users visits either Facebook or Linkedin.
b) Find the probability that an adult Internet user does not have an account with either social networking site.