i figured out this one too
Stockbrokers often try to provide a balance of stocks in a portfolio (i.e. a collection of stocks). A stockbroker has avaliable 4 Type A stocks, 3 Type B stocks, and 5 Type C stocks. The stockbroker also has 3 clients who want 2, 6, and 4 stocks, respectively. How many ways are there to create the three portfolios if:
a) there are no restrictions on which stocks the clients get?
b) each client must recieve one type B stock.