yes, o think prayer is just communicate with heart, not sound
Does God hear the prayer of a person who does not shout?
God knows our THOUGHTS. If He knows that, we can pray in our hearts and He will know what we are praying.
I am a bit curious as to why you said “shout” though.
Prayer is all about the heart no need to shout God knows the thoughts of our precious heart, God look at the heart.
Yes. Prayer is to God. If there is desire in my heart, God will hear.
Yes. I guess you heard many people pray very loud and think maybe that is the sincere way. But in bible, there is no record says that you must shout loud to pray, then God will hear. You can pray loud, but not because of praying loud, God hear the prayer. In bible Jesus taught us how to pray. And there are so many prayers in bible. If you read more, you doubts will be solved.
Yes, God hears. God knows everything about us. Even though we pray silently, he knows our heart and thinking.