A mathematics department has 12 members. The department wants to form a curriculum committee with 5 members, an executive committee with 3 members, and a textbook committee with 4 members. Each faculty member will serve on any of the committee.

Though the people doing the assignment didn't know 6 of the 12 own stocks in math company. what is the probability that exactly 3 of the stock owners will be assigned to the textbook committee.

In how many ways can membership be formed for the curriculum.

In how many ways can the complete roster of the committees be formed?