Hi, I need help with this question. Please

A health inspector at a restaurant will enter the kitchen and choose 5 stations to inspect from a predetermined list of 15 stations present in most restaurant kitchens. a. How many different sets of 5 stations exist? b. If all sets are equally likely, what is the probability of each set? c. If the inspector were instead to randomly select 13 stations .to inspect, how many different sets of 13 stations would exist?

d. If all sets were equally likely, what is the probability of each set?