The primary regions of origin of refugees applying to come to the us in 2007 were
a. africa and asia
b. africa and the middle east
c. asia and the middle east
d. africa and eastern europe

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.