A police checkpoint is set up on New Years Eve to catch drunk drivers. It is known that 2% of drivers on New Years Eve have a blood-alcohol level that is above the legal limit. It is also known that 28% of drivers in the area never drink and drive, but are simply bad drivers. The remaining 70% of drivers never drink and drive and are good drivers. At this particular checkpoint, the police stop 90% of the drunk drivers, stop 25% of the bad drivers, and stop 10% of the good drivers. 

(a) There are four events of interest in this problem. Specify the four events of interest and define notation for each of these events. 

(b) What is the probability that a randomly selected driver will be stopped at the checkpoint? 

(c) What is the probability that a randomly stopped driver has a blood-alcohol level above the legal limit?