Decide if each of the following is a permutation (P), combination (C), or neither (N), then fill in the appropriate letter in the blank.

There are 32 workers at a job, how many ways can they promote a manager, asst. manager, and supervisor?
There are 7 students in line for lunch, how many ways can this happen?
There are 20 students in a classroom, how many ways can 5 students be absent?
There are 3 different colored shirts at the store. You need to buy one for yourself and 6 others. How many ways can you do this if it doesn't matter what color each person gets?