Not likely. Unless the plant has a tolerance for salt because it is adapted to the salt marshes, salt will kill the plants.
yes but not for much
it is a snail without a shell
they are still slugs No, because slugs don't have shells on the outside of their body, they do have shells on the inside of their body though. Snails have shells on the outside and they don't grow...
Because they probably are stealing there shell praying over them or they are protecting them.