Final answer:
The possible selections of collars for the 5 dogs, with repetitions of colors allowed, is 32,768.
Step-by-step explanation:
If Ben wants to buy a new collar for each of his 5 dogs and there are 8 different colors to choose from, with repetitions of colors allowed, we can use the concept of permutations with repetition.
To find the possible selections of collars for the 5 dogs, we can multiply the number of options for each dog. In this case, there are 8 colors to choose from for each of the 5 dogs. So the total number of selections is 8^5 = 32,768.
Therefore, there are 32,768 possible selections of collars for the 5 dogs if repetitions of colors are allowed.