Tutor profile: Paul C.
Subject: Environmental Science
How does the ocean respond to rising atmospheric carbon levels, and what are the consequences?
The ocean is a sink for atmospheric carbon, meaning it takes it in and it dissolves into the water. Once in the water, some carbon is converted to carbonic acid, which has negative effects, lowering the pH of ocean waters and dissolving the shells and coverings of marine animals with carbonate shells.
If a population of beetles is eaten only when beetles are too large, what form of selection is occurring, and how will this affect the average size of beetles in future generations?
This is directional selection, and the beetles will be smaller on average in future generations.
If the distribution of IQ is approximately normal with a mean of 100 and standard deviation of 15, is Sarah's IQ of 140 statistically significantly higher than the average person?
Yes, an IQ of 140 is 2.67 standard deviations above the mean, meaning a z-score of 2.67. A score of this magnitude or higher has only a 0.38% chance of occuring due to random chance alone, so it is statistically significantly higher than the mean.
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