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Answer:</h2>
Removal of the tarnish from the silver is a <u>physical change</u>.
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Explanation:</h2>
The type of change which doesn't produce any new substance is called as physical change. Tarnish refers to the thin black layer that is formed on the silver. Formation of tarnish is chemical change as due to oxidation a black color layer is formed.
On the other hand, removal of tarnish from silver is considered as physical change as no new product is formed and only we are obtaining the silver in its pure form.
Answer:
The process of gene flow
Explanation:
Gene flow refers to the transference of genetic variation from one population to another. High rates of gene flow are known to modify the allele frequencies and reduce genetic differences among groups. Gene flow limits the process of speciation by combining gene pools form different groups. In humans, for example, it has been shown that migration in the past decreased genetic variation among their populations, thereby leading to the homogenization of genotype frequencies among geographic groups. It is for that reason that in population genetics the concept of 'human races' is now often recognized as erroneous and inadequate.
Answer:
Population- This is why we refer to the amount of people in an area as the area's population
