mezuzot

Question

Shalom - I had some doubts about the following mezuza scenarios [the Shulcha aruch is very terse!]: 1. for 2 enrances [without doors] that lead into and out of the kitchen [onr from dining area, one from living area] -i can not tell which side is theh 'right' side as we walk in and out both ways into and out of rooos simultaneously - how can i tell ? 2. walk-in closets -what is 4x4 amah in feet size ? 3. balconies - have a balcony on a pool deck in a condominium so i can walk out of my living room onto the balcony [which has a roof and a railing all the way around, but if i wanted to i could exit the building complex by leaving the balcony to the pool out a back door or into a building hallway door - which side of the balcony-living room door entrance do i place the mezuza ? thank you.