Suppose you are traveling on business to a foreign country for the first time. You do not have a bus schedule or a watch with you. However, you have been told that buses stop in front of your hotel every 20 minutes throughout the day. If you show up at the bus stop at a random moment during the day, determine the probability that

a. you will have to wait for more than 10 minutes

b. you will only have to wait for 6 minutes or less

c. you will have to wait between 8 and 15 minutes