How many different displays can be made if:Quote:

Johnathan has 18 different trophies on his shelf. Four of the trophies are for racing, nine are for high jumping, five are for cycling.

1, Six trophies are chosen?

$\displaystyle nPr(18,6)=13366080$

2, Six trophies are chosen, two from each activity?

I'm not sure how to do the second one, please help.