Suggest, and explain, two reasons why a much smaller population of Nitella plants is found amongst the Potamogeton plants than further down in the lake.

Explanation:

If an igneous rock is exposed to the sun for millions of years it becomes brittle. This causes it to break down more easily. Then the energy from the Earth's interior would cause a weathering and erosion effect on the rocks. This would ultimately go breaking down the rocks over time turning it from igneous rock to sedimentary rock that is all small broken pieces of the igneous rock. This entire process would take millions of years to occur.