Four people, in turn, are going to choose a marble randomly from a jar containing nine marbles, labeled 1 2 3 4 5 6 7 8 9. Each person will replace his/hers marble after choosing. In how many ways can these four people choose?

Sorry this is a write in not a multiple choice!

36 ways

Step-by-step explanation:

This is probability with replacement

Each of them want to choose a marble randomly from a jar containing nine marbles

The number of ways these four people can choose will be

4( 9 combination 1) that is

4( 9C1) = 4[9!/(9-1)! 1!]

= 4[9!/8!]

= 4(9)

= 36 ways

a. is correct