Sample question for a test. Not sure how to approach:
A mutant volleyball team of 3 heros and 3 villains is to be chosen from a group of 9 heros and 5 villains.
How many different teams are possible?
How many different teams are possible if two of the heros refuse to be on the same team?
How many different teams are possible if two of the villains refuse to be on the same team?
How many different teams are possible if one hero and one villain refuse to be on the same team?