Source: Data extracted from $"2016$ Social Media Marketing Industry

Report,"

socialmediaexaminer.com.

$4\mathrm{.}11$ Referring to the contingency table in Problem $4\mathrm{.}10,$ if a mar$-$

keter is selected at random, what is the probability that

a$.$ he or she plans to increase use of LinkedIn?

b$.$ he or she is a B$2$C marketer?

c$.$ he or she plans to increase use of LinkedIn or is a B$2$C marketer?

d$.$ Explain the difference in the results in $($b$)$ and $($c$).$