So I'm really lost on my homework  right now...so I got a few questions I hope you can help me...

So I'm really lost on my homework  right now...so I got a few questions I hope you can help me with :).  How did the "Rightly Guided Caliphs" come to power and also for the Dynastic Caliphs. What were the important names(for both)? And what were the location of the capitals(in Islam long time ago...)? Who were the external attackers that defeated the Caliphate(there are two)? Individual Islamic states governed by a _____? The greatest Islamic state became the _____? What happened after the Mongol invasion destroyed the caliphate? I know this is really long , but I REALLY need help badly. Tell me as soon as possible please! Thanks.