The answer is; Cosmic background radiation is leftover thermal energy from the big bang.
Called the coming microwave background the weak radiation fills the universe more or less uniformly. This radiation is the fossil remnants of the postulated big band at the beginning of the universe. The photos produced at the time continue to travel through the universe growing fainter over time and have fallen in the microwave range of the electromagnetic spectrum now.
Fluorine.
Because:- Atoms want to become stable, for an atom to become stable, they need 8 valence electrons. Since Fluorine has 7 valence electrons, it only needs one more electron to become stable and have an octet. An octet is when an atom/element has 8 valence electrons. Since Fluorine will need to gain an electron, it will have a negative charge, and become an anion.
Plants obtain energy from the sun during photosynthesis and pass it along the food chain.
<h3>What is a model?</h3>
A model is a representation of reality. We use models to understand what the real situation of things is like.
Let us recall that plants are the producers in the ecosystem. Energy flow from plants to animals. Plants obtain energy via the reaction 6CO2 + 6H2O --->C6H12O6 + ATP. This energy is passed along the food chain as organisms feed on each other.
Learn more about models: brainly.com/question/14281845
The subscripts indicate the number of atoms of the element immediately before it.
I would say developed technologies which somehow were lost
like the stone age: the stone hammer, who used that afterwards in the roman empire era and stuff?
