yes you can as lond as they have not been spoiled or nothing is in the water, except for water
YESSSS
You should pat them dry or your grease is going to splatter
The potatoes become flacid because the salt water drins out the moisture from the cells of the potatoes. This process is called exo-osmosis . The cells lose their turgidity and hence the potatoes become flacid :)
No, just make sure they are totally under water and under refrigeration
yes, they should be soaked over night
Lima beans absorb water because they are dried so when you put it in water it rehydrate
I'm not sure about salt water but i got loads of water in my electric toothbrush once and it was soaked but it still worked
Yes you can.
By leaving the potatoes on an extremeily low heat and slow cook them.
Yes, however, I tend to cover them with water to prevent them drying out.
I wouldn't recommend having a marinade on potatoes overnight. You can cut your potatoes up the night before and have them soak in water to avoid turning them brown/black. Just make sure the water is about an inch over the potatoes. If you want to marinate, an hour of soak time is good enough for potatoes. It's the oxygen that is touching the potatoes that turns them, so there might be some areas of the potato not completely covered in oil. If you still want to try it, make sure to have an airtight lid on.
to get rid of bugs