The survey by the National Center for Health Statistics further found that 49% of adults ages 25-29 had only a cell phone and no landline. We randomly select four 25-29-year-olds:
a) What is the probability that all of these adults have a only a cell phone and no landline?
b) What is the probability that none of these adults have only a cell phone and no landline?
c) What is the probability that at least one of these adults has only a cell phone and no landline?