With regard to the evolution of skin color in humans, which of these conditions is Nina sure about (and why?) and which one(s) is she investigating?

Ecosystems involve living organisms interacting with non-living things in a productive way; how is photosynthesis an example of this? answer, i will give brainiest to first person to get it right.

What is the following best defines climate?

Use the distance formula to determine weather each pair of segments have the same length