in the first problem,ordermatters.

12 possibilities for the winner

11 possibilities for 2nd place

10 possibilities for 3rd place

if the winning employees were a, b, and c in that order, that would not be the same as b, c, and a in that order.

when order matters, you are dealing with a permutation.

in the second problem, orderdoes notmatter ...

nurses a, b, and c are in the same group as nurses b, c, and a

when order does not matter, you are dealing with a combination.