1-Without gravity you can't grow any plant or tree because dirt would fly away
2-We are using gravity for a lot of physics system too
3-All the water on Earth would have been flying in the space
4-There wouldn't be atmosphere.
A its Stratosphere, Sorry I didn't see your answer, its bilogy I think not physics.. :)
Answer:
2000metres
Explanation:
Pressure= density x height x gravity
Gravity is always a constant = 10N/kg
so height= Pressure/( density x gravity)
h= 20000000/(1000 x10)
h= 2000 metres
Sound waves....................................
