Mexico city's most pressing environmental issue is
a) mountain erosion.
b) dangerous air pollution.
eliminate
c) erosion along the coastline.
d) cutting down of the rainforest.

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.

it looks like its all of the above. [.wpal1kojopfdpojfrfionrnif.knfdsnksjosjo]

explanation:

you have to combine all of your answers together to

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