Answer: Outside Invaders Threatened Border Areas
Explanation: There were string of military losses sustained against the Germanic Tribes. Rome has been at constant war with the Germanic Tribes for centuries and by 300 AD, a Tribal group called the Goths had encroached the borders of the Roman Empire. In the year 410, Visigoth King Alaric sacked the city of Rome. Then the Vandals tribe sacked Rome in 455 as well. It was in 476, when the Germanic Leader Odoacer staged a revolt and deposed of the Emperor Romulus Augustulus. It is at this moment that Western Rome falls and the Medieval Age begins as Europe falls into a dark age.
A.Irrigate
They need to make an irrigation system to water their crops
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