They are alpha world cities of london and paris so that would be like mexico city or dublin,vienna,seoul,tehran
I would say that the Rocky Mts were the youngest of all these mountain ranges as they were created between 80-55 million years ago during the Laramide Orogeny and also they are generally much taller than the other mountain ranges mentioned here which is a characteristic of young mountain ranges and their features are sharper as they haven't been eroded the way most of these others have so have been subject to erosion for less time than the others.
Answer:
all Four...
Explanation:
all four are true...
they occur simultaneously
