Answer:
The correct answer is option D, Unconfined aquifers are found between two layers of impermeable soil or rock.
Explanation:
An unconfined aquifer is not confined by rock layer on both of its side. Usually the ground water level (GWL) is considered as the upper layer of unconfined aquifer. Also the rocky layer found on the other side of the unconfined aquifer is not impermeable as the major source of recharge of unconfined aquifer is the seepage of water through is permeable layer or through rain.
The bell shaped curve indicates polygenic traits. A polygenic trait is controlled by multiple alleles. Hope this makes sense :)
The tree of life is a metaphor which expresses the idea that all life is related by common descent. Charles Darwin was the first to use this metaphor in modern biology. It had been used many times before for other purposes. The evolutionary tree shows the relationships among various biological groups.
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I hope this helps.
Carbon, hydrogen, and oxygen are used during photosynthesis