Based on evidence of the redshift of stars and galaxies, scientists know that the universe is expanding. The redshift shows that galaxies outside the Milky Way is moving away from us. The farther the galaxy is the faster it is moving away.
Answer: No
Explanation: Because your parents said so
The correct answer for the question that is being presented above is this one:
(1) contracting cloud of gas and dust
(2) protostar
(3) main-sequence O star
(4) red supergiant
(5) supernova
<span>(6) neutron star</span>
Here are the following items to be arranged:
<span>- protostar
- supernova
- contracting cloud of gas and dust
- main-sequence O star
- red supergiant
- neutron star</span>
<u>Answer:
</u>
The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
</u>
- The ozone layer is a part of the stratosphere which is located right after the troposphere in the atmosphere of the Earth.
- The ozone gas is made up of the abundance of three oxygen molecules combining with the ultraviolet radiation emitted by the Sun.
- The development of the ozone layer happened around two billion years ago when the oxygen concentration levels on the planet began to rise slowly and gradually.
