D, because skin tans to help us stand being in the sun without getting burned.
An example of physiological adaption is being able to digest milk. Before, humans were not able to digest milk before we developed enzymes that now make us have the ability to do so, thus allowing us another food source.
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observation because you are using senses such as sight and smell to come to a logical conclusion about something.
The answer is D I just took the test
Answer:
A polar molecule simply means the charges are not exactly even throughout the molecule. Some parts are slightly negative (outside the oxygen), and some parts are slightly positive (outside the hydrogen atoms). Water is polar because the highly electronegative oxygen atom attracts electrons to it, making the region around the oxygen more negative than the areas around the two hydrogen atoms. This concept is important to understand how water bonds.
