i must admit i dont really understand how boats dont sink and how airplanes stay up

[Altruist]

i memorized it had something to do with density (boats) and engines (planes), but the concepts didnt really sink in

shouldn't a boat automatically sink if there is even a single barrel of drinking water of it?

why do planes have wings when they are static? is it just for decoration/to imitate birds? because you could get rid of them by putting engines on the sides (if my assumption that they are used to change direction is correct)

- my pet