Does a subwoofer fit in a Ford Explorer XLT 2003 With the 3rd row seat? please answer fast?

i have a Ford Explorer XLT 2003 with 3rd row seats i dont know if its possible to fit a subwoofer in there with out removing a seat and that you can sit down any sit i would like to know if i could put it all the way in the back and if it fits and what kind or do i have to make an encloser or how many subs could fit there and what size or any i need specific deatails not too genius of an answer that i will not be able to under stand please make it detailed and simple.