In how many ways can 3 boys and 3 girls sit in a row if the boys and the girls are each to sit together? In how many ways if no two people of the same sex are allowed to sit together?

a club consists of 5 men and 4 women. in how many ways can this club elect a president, Vice President  and secretary in that order if the president must be a man and the other two officers must be a woman?

How many committees can be formed from 12 men and 12 women if the committee must consist of 3 men and 4 women?

If a team of four players must be made from eight boys and six girls, how many teams can be made if they must all be boys?