Fossils help scientists date rocks: True
Sometimes younger rock layers are found beneath older rock layers: True, because it happens with landslides and other causes.
No fossils from the Precambrian era have been found because there were no organisms at the time: False because there were organisims like algae and bacteria, and there are a very small amout of fossils from that era.
The map of Earth has changed over millions of years, but is now set: False
Answer: tropical grasslands
Explanation: i took the test :)
The answer is A; a natural source
The Sites pebbles is the type of sediment sample that normally has the greatest permeability rate.
<h3>What is a permeability rate?</h3>
This refers to the rate at which an applied irrigation water moves through the soil.
Hence, the sites pebbles has the greatest permeability rate because it has allows a large space which helps moves unto the beneath easily.
Therefore, the sites pebbles is the type of sediment sample that normally has the greatest permeability rate.
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