You are managing a train yard. Currently there are 4 tank cars, 12 boxcars, and 7 flatcars present on the lot. a.) How many ways are there to randomly select 10 types of cars for the train (without regard to order)? b.) How many different combinations are there for a train that is composed of 2 tank cars, 5 boxcars, and 3 flatcars? c.) What is the probability that of 10 cars selected, 2 will be tank cars, 5 will be boxcars, and 3 will be flat cars? d.) If the order of cars matters for considering an aspect of risk, how many ways are there to organize 10 train cars