Question

15 multiple choice 1 point a dead zone is caused by: lack of sunlight hurricanes high oxygen levels oxygen depletion 16 multiple choice 1 point well-oxygenated water contains how much oxygen? 1 ppm 10 ppm 2 ppm 5 ppm

Explanation:

Question 15

A dead zone in aquatic environments is an area with little to no oxygen, making it uninhabitable for most aquatic life. Lack of sunlight doesn't cause dead zones (it affects photosynthesis but not directly oxygen depletion to create dead zones). Hurricanes don't create dead zones; they are storm events. High oxygen levels are the opposite of what a dead zone is. Oxygen depletion (hypoxia) is the cause of dead zones, often due to nutrient pollution leading to algal blooms that decompose and use up oxygen.

Well - oxygenated water typically has an oxygen concentration around 10 ppm (parts per million) or higher under normal conditions. 1 ppm, 2 ppm, and 5 ppm are relatively low and not indicative of well - oxygenated water.

Answer:

D. Oxygen depletion (assuming the options are labeled A - D as: A. Lack of sunlight, B. Hurricanes, C. High oxygen levels, D. Oxygen depletion)

Question 16