He who wanna talk?? 1+1

Which statement accurately describes the relationship between air pressure, air density, or altitude? as altitude increases, pressure increases.as altitude increases, air density increases.air pressure and density are lowest at sea level.denser air exerts more pressure than less dense air.

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

Explain why scientists use shared characteristics to make cladograms.