<span>If you google your question this comes up - Name the four classes of carbon-containing molecules used by living things, and explain how the nitrogen and carbon cycles contribute to the usable supplies of these macromolecules. The carbon-containing (organic) macromolecules necessary for life are proteins, carbohydrates, lipids and nucleic acids.</span>
the answer is D. Air will move from an area with higher pressure to an area with lower pressure :)
Answer:
Septic tanks and oxidation ponds
Explanation:
These system of wastewater treatment and disposal are not too feasible in large municipalities because of the presence of sewer system that has been made available by government, in order to mitigate the possibilities of transmitting enteric diseases that are very harmful to human health.