A dependent clause often helps qualify an infinitive or participle

B) raising the temperature and reducing the volume of the gas.|-/ 

Sounds propagates through some kind of medium. usually it's air, but it goes just as well through solid objects like walls, windows etc. a soundwave will compress the (air)molecules in front of it, and if this increased density wave hits your ears, you register it as sound. solid objects like walls are a lot denser than air, this means that they will damp a wave, but also carry it easier.

  soil is  vegetal. in forest or prairies, as well as agricultural fields, dead plants are transformed by different kinds of living organisms.