For each event,circle the most appropriate term.

Question

21. Six friends go to a movie.How many ways can they sit in a row of six seats?

counting principle,combination,factorial, or permutation

Answer 1

permutation
number of ways to seat 6 people
= 6! = 720

Answer 2

I don't understand this question.For each event ,circle the most appropriate term.
19. 6*5*4*3*2*1

Counting principle, combination, factorial,permutation.