How many generations has it been since chimpanzees split from humans?

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.

Type the correct answer in the box. use numerals instead of words. fiona has a lovely flower bed in her yard. she wants to add a fence along one side of the flower bed. the fence material is sold in meters. fiona knows that her flower bed is 200 centimeters in length. how much fencing material does fiona need in meters? fiona needs meters of fencing material for her flower bed.

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?