I have a 10 x 10 concrete patio that sits against the house. I want to expand the patio on the three uncovered sides. I live in the mid-west( Lafayette, Indiana) so I need to account for hot, humid summers and cold freezing winters.

My questions are:
1)Do I make the surrounding additions one big slab or break it into three separate slabs.
2)How do I tie the new concrete into the existing patio to prevent cracking and make it look good.
3) How deep do I need to dig the new slab area? Do I need to put down stone or pour onto the leveled dirt?

Thanks for the help.