What was the most difficult challenge of Greece's geography?

Controlling the Aegean facilitates trade, defense and communication. Protecting this core from invasion is Greece's main geographic challenge. Because of its strategic location in the heart of the Mediterranean, Macedonian, Roman, Byzantine and Ottoman empires ruled Greece for more than 2,000 years.

Explanation:

yes i think there would be volunteers

a direct vote in which an entire electorate is invited to vote on a particular proposal. this may result in the adoption of a new law.