Here are the short answers to your questions:
1) A fruit is a ripened ovary containing seeds after fertilization.
2) A true fruit develops solely from the ovary, a false fruit involves other floral parts like receptacle.
3) Gymnosperms lack ovaries so they cannot produce fruits.
4) Protect seeds, help in seed dispersal.
5) A simple fruit develops from a single ovary, an aggregate fruit from multiple ovaries in one flower.
6) Fruit setting, cell division, cell expansion, maturation.
7) Transition of ovary to developing fruit after fertilization.
8) GA, cytokinin, auxin, ethylene