Answer: Photosynthesis
Explanation: Photosynthesis removes CO2 from the atmosphere and replaces it with O2. Respiration takes O2 from the atmosphere and replaces it with CO2.
This produces several negative effects on the biodiversity of the river ecosystem.
<u>Explanation:</u>
The Susquehanna river is polluted by the excess release of nutrients like phosphorous and nitrogen from agricultural land and sewage treatment plants. This can adversely affect the health of the river. The excess of nutrients will accelerate the growth of algae in the river.
The dead algae that settle at the bottom of the river decay by consuming the oxygen present in the river. This will reduce the amount of dissolved oxygen in the river and affect aquatic life.
Thick algal growth partially prevents the penetration of sunlight into the water and this affects the growth of submerged plants which are food to the fish.
It is not C. I got it wrong. It is A water!
Answer: Option (C)
Explanation: The rocks at the continental crust are present since a long time, and the oldest rocks so far encountered from the continental crust is approximately 4.4 billion years old.
This has been determined by the Uranium-Lead dating method (Ur₂₃₈-Pb₂₀₆).
Oceanic rocks are estimated to be of very recent age i.e about only 180 million years old.
