1. Roller Coaster The Rock 'n' Roller Coaster at Disney-MGM Studios in Orlando has two seats in each of 12 rows. Riders are assigned to seats in the order that they arrive. If you ride this roller coaster once, what is the probability of getting the coveted first row? How many times must you ride in order to have at least a 95% chance of getting a first row seat at least once?
2. Whodunnit? The Atlanta plant of the Medassist Pharmaceutical Company manufac- tures 400 heart pacemakers, of which 3 are defective. The Baltimore plant of the same company manufactures 800 pacemakers, of which 2 are defective. If one of the 1200 pacemakers is randomly selected and is found to be defective, what is the probability that it was manufactured in Atlanta?