( ( ( The speed ) ( of sound ) ) ( ( ( depends ( on ( ( the type ) ( of gas ) ) ) ) ( ( ( in ( ( the atmosphere ) ( -LRB- ( ( ( ( nitrogen and ) oxygen ) ( for ( ( the ( Earth ( and ( carbon dioxide ) ) ) ) ( for Mars ) ) ) ) -RRB- ) ) ) ) and ) ( on ( ( the ( square root ) ) ( of ( ( the temperature ) ( of ( the gas ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN speed)) (PP (IN of) (NP (NN sound)))) (VP (VBZ depends) (PP (IN on) (NP (NP (DT the) (NN type)) (PP (IN of) (NP (NN gas))))) (PP (PP (IN in) (NP (NP (DT the) (NN atmosphere)) (PRN (-LRB- -LRB-) (NP (NP (NN nitrogen) (CC and) (NN oxygen)) (PP (IN for) (NP (NP (DT the) (NN Earth) (CC and) (NN carbon) (NN dioxide)) (PP (IN for) (NP (NNP Mars)))))) (-RRB- -RRB-)))) (CC and) (PP (IN on) (NP (NP (DT the) (JJ square) (NN root)) (PP (IN of) (NP (NP (DT the) (NN temperature)) (PP (IN of) (NP (DT the) (NN gas))))))))) (. .)))
The speed of sound depends on the type of gas in the atmosphere (nitrogen and oxygen for the Earth and carbon dioxide for Mars) and on the square root of the temperature of the gas.
(ROOT (S (NP (NN Nitrogen) (NN gas)) (VP (VBZ comprises) (NP (NP (QP (RB about) (NNS three-fourths))) (PP (IN of) (NP (NP (NN earth) (POS 's)) (NN atmosphere))))) (. .)))