A  Pew Research Center survey (Pew Research website) examined the use of social media platforms in the United States. The survey found that there is a  0.68 probability that a randomly selected American will use Facebook and a 0.25  probability that a randomly selected American will use LinkedIn. In addition, there is a  0.22 probability that a randomly selected American will use both Facebook and LinkedIn. 

a. What is the probability that a randomly selected person will use Facebook or LinkedIn (to 2 decimals)? .71

 b. What is the probability that a randomly selected person will not use either social media platform (to 2 decimals)?