combinations and probability

A pet store has 14 dogs and 9 cats. One day, seven of these pets are adopted. (The 4 - X order of adoptions is not important, so we should use combinations.) 9 a) In how many ways can 7 pets be chosen? b) In how many ways can 4 dogs be chosen? c) In how many ways can 3 cats be chosen? d) In how many ways can 4 dogs and 3 cats be chosen? e) Find the probability that 4 dogs and 3 cats are chosen