1. explain the role of a prophet.

2. give one example of a prophet and tell what he did.

Well, all prophets are also Messengers, Prophets send messages from god, therefore makes them a messenger too. A prophet's role is to deliver the words and wisdom of god to the people who are unaware of gods power and greatness. 

For an example, there is Prophet Muhammad (Sallalhu alahi was salam) he was the greatest prophet/Messenger to ever walk the face of this earth, he delivered speeches and lectures to the people to turn to god before it was too late and he was just an amazing guy, the noblest and most beneficial person to ever speak words of Wisdom.I hope I've helped and thank you for visiting !