Well, the three problems that mainly affected Germnay and gave Hitler a stronghold starts with the Treaty of Versailles. After losing WWl, Germany was forced to sign the treaty that plunged their land into poverty. So, the three things on this treaty are your three problems. They are:
1. Germany was forced to give up a large amount of its army
2. Germany was forced to give large amounts of thier land to the French.
3. Germany had to pay large sums of money for war reperations.