Question

4 multiple choice 2 points which of the following is not a common water pollutant? bacteria oxygen sediments chemicals 5 multiple choice 2 points which of the following is an example of nonpoint source pollution? pesticide runoff from residential lawns a sewage treatment plant discharging treated wastewater into a river oil spills from ships in the ocean a specific industrial discharge pipe releasing chemicals into a lake 6 multiple choice 2 points what is eutrophication? the natural aging of a water body over time a process that increases oxygen levels in aquatic ecosystems a process that decreases water temperature in lakes the excessive enrichment of water bodies with nutrients

Explanation:

• Question 4: Bacteria (e.g., fecal coliform), sediments (from erosion), and chemicals (like pesticides) are common water pollutants. Oxygen is essential for aquatic life and not a pollutant.
• Question 5: Nonpoint - source pollution comes from diffuse sources. Pesticide runoff from residential lawns is from many small, unidentifiable sources. Sewage treatment plants, oil spills from ships, and specific industrial discharge pipes are point - source (identifiable single source) polluters.
• Question 6: Eutrophication is the excessive enrichment of water bodies with nutrients (usually nitrogen and phosphorus). This leads to algal blooms, oxygen depletion, etc. The natural aging of a water body is a different concept (natural eutrophication is slow, but anthropogenic eutrophication is accelerated). It does not increase oxygen levels (algal decomposition consumes oxygen) and is not related to water temperature decrease.

Answer:

• Question 4: B. Oxygen
• Question 5: A. Pesticide runoff from residential lawns
• Question 6: D. The excessive enrichment of water bodies with nutrients