-The elements in the set (X / X is an integer less than 5 are)=?

-Find A n B where,
A = (X / X is an integer thats multiple of 3)
B = (X / X is an integer thats multiple of 7)

-A box contains 5 red and 7 green balls.How many ways can two balls be
selected with the two balls the same color.
- How many ways can first and second awards and 3 consolation award be
given to 9 contestents?

- In how many ways a CEO , a CFO and 3 board members be selected from
a group of 8 people?