Answer:
1. a pact made between 'Abd al-'Aziz (son of Musa bin Nusair, governor of North Africa) and the Christian Visigoth Theodemir, Tudmir in Arabic (prince and governor of the region of Murcia in the Iberian Peninsula) in the early eighth century.
2.The Muslims will treat the people they conquer with respect and will protect them.
3. The account of Muslim expansion in this document is different from what I expected based on the map alone. I expected the expansion to occur through many aggressive battles but according to this document they earned the land with respect and trading.
4. I think this document is a reliable source for determining how the caliphates expanded because the date of this document is from around the time the expansion happened, and they would know more than we do since they experienced it as it happened.
Hypothesis#3: Through trade and trade routes alongside expansion.