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.
Answer:
D) Comes from oil rigs in the Atlantic Ocean!
Explanation:
Oxygen is transported in the blood in two ways: A small amount of O 2 (1.5 percent) is carried in the plasma as a dissolved gas. Most oxygen (98.5 percent) carried in the blood is bound to the protein hemoglobin in red blood cells. A fully saturated oxyhemoglobin (HbO 2) has four O 2 molecules attached.
(https://www.cliffsnotes.com/study-guides/anatomy-and-physiology/the-respiratory-system/gas-transport)