On what do you need help on because it doesn't show on what do you need help.
Answer:
1) The forming of a theory or conjecture without firm evidence. Or, investment in stocks, property, or other ventures in the hope of gain but with the risk of loss.
2) Speciation occurs when two or more populations become so genetically distinct that they no longer interbreed with one another. There are multiple ways this can occur. The natural ways speciation can occur are allopatric, parapatric, and sympatric speciation.
3) Before the Great Depression, there were limited regulations that governed the stock market. Investors were able to speculate wildly and buy stocks on margin or using borrowed money. ... The poor policies that governed the stock market proved to be another of the causes of the Great Depression.
I think 1 and 2 might be wrong but, hope it helped!
Answer:
Zicrons
Explanation:
The oldest of the zircons in the study, which came from the Jack Hills of Western Australia, were around 4.3 billion years old—which means these nearly indestructible minerals formed when the Earth itself was in its infancy, only roughly 200 million years old.
The main reason why the tectonic plates move is the conversational currents. There is magma between the upper mantle and the asthenosphere that heats up at the upper mantle. The weight is so small that the magma rises with the help of these conversational currents. When the magma has ascended towards the asthenosphere, it has nowhere to go so the magma lies along the asthenosphere. There the magma cools down again because the asthenosphere is colder than the upper mantle, which makes the magma heavier and goes back down to the upper mantle, where the magma heats up again and everything starts all over again and so it goes on over and over again. Scientists have concluded that the earth's gravity causes two other processes that also cause the tectonic plates to move.
Ridge push - in the spreading zones, the sides of the tiles are raised and slide to the side as in a slide.
Slab pull - when a plate is pulled down by gravity in a subduction zone like an anchor.