Answer:
4
Explanation:
There will be the number of ways to arrange n objects. In fact, the factorial method is used to calculate the number of ways for arranging n objects will be like this:
n! = n * (n-1)* (n-2)* (n-3) * ...*3*2*1
Another method will be to sue the binomial method or combinations:
(n r) =

To arrange 4 colors over 3 edges, this means that:
n =

= 4
Therefore, there will be 4 ways of arranging the numbers.