Given:
Number of cities = 12
Let's find the number of possible routes.
To find the number of different possibel routes, apply the permutation formula.
12!
Therefore, we have:
12! = 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1 = 479001600
Therefore, there are 479,001,600 different routes.
ANSWER:
479,001,600