Tentative Answer - Quran

4. What characteristics of the text make it more likely that one should believe what it says?

The text uses familiar parables that we have learned from reading the Bible and draws on human emotions in order to convince readers to believe what it says. There is fear of missing out of a good afterlife; those who fear Allah or are his "companions of the right hand" will have bliss and an abundance of food, drink, and peace - there is a great and desirable idea of the Gardens of Bliss Eternal. On the other hand, if you do not obey and respect Allah then you are considered a "companion of the left hand", because you have rejected the truth and will therefore always be uncomfortably hungry and thirsty and drinking boiling water in "hellfire". 
Secondly, the rules of a good life in the Quran sound pretty easy to accomplish and good to follow - it's not making us do anything bad and the rules benefit us as people. Even if a person does not know of Allah yet, these rules are pretty natural to follow, such as serving others with sincere love and kindness. Also, Allah is a good source of hope and motivation, telling us not to despair in misfortune and also to temper our happiness during good times; this gives everyone an anchor when they receive Allah as refuge and help. 
Third, even if you have already done wrong, Allah is said to be a merciful being as long as we respect and seek repentance. We are not doomed just from doing wrong; if we are sincere we can still be saved and given another chance. 
Lastly, the text thoroughly predicts and addresses thoughts humans may have in the future when they die and explains through most of these "what if"s, helping you realise there is no excuse for your actions - it was your "obstinacy, vanity, and insolence" (96) that prevents you from seeing the truth. It says to live life to the fullest and serve others well, because we will die for sure even though we don't know when we will die, and there will be a Judgement Day. When it comes, we aren't able to go back to say "If only Allah guided me, I would have been good" or "if only I had another chance, then I would do good" because the signs were always there so you don't really have an excuse to be unfaithful. You had to have faith during your life, not just as a result of seeing the afterlife and realising the rewards after death are much greater than anything that could have been experienced in this world. The signs were always clear back then before Judgement Day,shown through the parables with stories like those of Moses, Joseph, Abraham, and Noah, to illustrate points about how the signs of God are clear and should be respected and if you do not obey then you will be punished or die of drowning (Red Sea, Noah's Ark, etc). The book urges us to open our eyes to the very clear signs we can see here, enforcing the idea that we are responsible for our actions because the guidance has been given to us - we have just chosen to see it or not. 

I'm still a bit confused because the Quran tells a lot of stories that we have read in the Bible, so are we worshipping the same God with a different name? However, it says Allah has no son, father, or partner - but God is the Trinity (Father, Son, and Holy Spirit). It also says that the Christians (People of the Book) have only part of the book, where Allah has the full book, and it's fine if Christians accept the full book but if they reject it then they must be separated from the People of Faith.