Answer:
Petroleum gas is mainly C3 and C4 based (propane and butane), whilst natural gas is predominantly C1 and C2 (methane and ethane). Petroleum gas is generally produced via the cracking of naphtha, which is one of the components separated during crude oil refining.
Explanation:
D. Enzymes and antibodies
Assuming its "resting" is the place in the middle of the wave crest and trough, the distance between the crest and the middle line would be considered its amplitude. The height of a wave is the distance between the crest and the trough, and wavelength is the distance between two crests.