Energy flow write the term that matches each meaning sum of all ecosystems in the world

1) sum of all ecosystems in the world : Biosphere
Biosphere is the worldwide sum of all ecosystems. It can also be termed the zone of life on Earth. The biosphere overlaps the lithophere, atmosphere, and hydrosphere.
2) All populations within an ecosystem : Community
A community is all of the populations of various species that sleep in a similar space and act with each other. A community consists of all of the organic phenomenon factors of a part.
3) Interbreeding members of a species in an ecosystem : Demes
A deme could be a term for an area population of polytypic species that actively crossbreed with each other and share a definite cistron pool.
4) A defined area consisting of biotic and abiotic components : An ecosystem
An scheme could be a community created from living organisms and non-conscious parts like air, water, and mineral soil.

Ithink its because more have died recently than in the past.

Answer:

the statements that apply here about binary star system are

"have stars that might appear to wobble"

"often have one star that is brighter than other"

a binary star is a star system consisting of two stars revolving around their common barycenter. systems of two or more stars are called multiple star systems.