please answer

6. At a bus stop, the waiting time in minutes for a new bus to arrive can be modelled using an exponential distribution with parameter )1. = 11:]. (a) You know the last train left at 7:01] AM. What is the probability the next bus comes before 7:15 AM? [b] What is the expected waiting time between buses ooming the bus stop? {e} You have already waited 5 minutes for a bus, what is the probability that you will have to wait more than 3D minutes in total for the train to leave the station? [d] Not every bus ooming to your stop will go to your destination. For every four {4} buses that leave the station, the fourth bus in this sequence will go to your destination. You just missed this fourth bus. How long do you expect to wait for the fourth bus in the sequence to come to your stop? Assume that the waiting times between each buses are independent and identically distributed