Explanation:
Given the importance of oxygen for animals, researchers suspected that a sudden increase in the gas to near-modern levels in the ocean could have spurred the Cambrian explosion. ... This supported the idea of oxygen as a key trigger for the evolutionary explosion.
Answer:
8 (not including Pluto because its not a planet)
There are many push factors when it comes to emigration, but first, a push factor is something that will make someone want to voluntarily leave because of the things happening in their country. Examples of some push factors are a lack of job opportunites, war, famine, and instability in the country. Examples of push factors in real life happening today are...
1. Syria - war/conflict from the Syrian Civil War
2. Venezuela - crime, and politcial and economic instability
3. North Korea - harsh laws and punishments, dictatorship, and the regime/totalitarianism
Hope this helps, have a BLESSED and wonderful day! :-)
