Answer:
I'm written with two letters, said with one and seen with two. What am I?
I save lives on the ground and in the air
My first though water cures no thirst my next alone has soul and when he lives upon my first he then is called my whole.
I am rubber you can eat!
I am black, white, and read all over. What am I?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.