A random sample of 350 workers at a car parts manufacturing plant are surveyed. Of the 350, all come to work by car. 246 commute more than 40 kilometres to work. 150 of the employees arrange rides with other workers. 135 of those who commute more than 40 kilometres to work drive alone.
a. What is the probability that a randomly selected employee from the sample commutes more than 40 kilometres to work?
b. What is the probability that a randomly selected employee from the sample arranges rides with other workers?