#25

How many ways can an advisor choose 4 students from a class of 12 if they are all assigned the same task?

How many ways can the students be chosen if they are given a different task?

#37

There are 7 women and 5 men in a department. How many ways can a committee of 4 people be selected? How many ways can this committee be selected if there must be 2 men and 2 women in this committee? How many ways can this committee be selected if there must be at least 2 women on the committee?