Human wastewater results in which water-pollution problem? i. decomposition of organic matter reduces dissolved oxygen levels. ii. decomposition of organic matter releases great quantities of nutrients. iii. pathogenic organisms are carried to surface waters.

The correct answer is - all the options.

Explanation:

Any water that is used by humans or affected by humans is termed as wastewater. It includes water that comes from domestic households, agricultural and industrial water that can lead to pollution to the lakes, rivers, and other water bodies.

Untreated water contains pathogenic organisms that cause contamination to the people and the environment. It reduces the oxygen level in water bodies that are called dissolved oxygen. Decomposition of the waste present in the water release a high quantity of minerals that affect the environment and organisms.

Thus, the correct answer is - all the options.

propane is burned to provide the heat in many cooking grills. the chemical reaction for this process is shown in the equation below.

c3h8 + 5o2 ? 3 co2 + 4h2o + energy

what are the products in this chemical reaction?

3co2 + 4h2o + energy