Which two factors contributed to the fall of the Roman Empire?

Explanation:

Invasions by Barbarian tribes. The most straightforward theory for Western Rome’s collapse pins the fall on a string of military losses sustained against outside forces.

Economic troubles and overreliance on slave labor. Even as Rome was under attack from outside forces, it was also crumbling from within thanks to a severe financial crisis.

no statements but ok.

the statement that best describes the idea of manifest destiny that was used in the 19th century would be that "it was fate that the united states would continue to  expand westward," since people thought the us was "destined" to do so. 

i think it would be a