Answer:
Explanation:
The population density of an area is a demographic tool used to measure the number of organisms or individuals in a particular area.
It is expressed as;
Population density = 
The unit is expressed as organisms/km²
An area with a high population density is often not desirable as it can lead to pressure on amenities and infrastructure.
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Bromothymol blue is an indicator dye that turns yellow in presence of an acid. It remains blue if the pH of the given solution is greater than 7.6 and yellow when the pH is less than 6. The yellow coloration is due to the formation of carbonic acid in the from the carbon dioxide present in the solution.
When aquatic plants are added to two test tubes containing bromothymol blue, stoppered and kept in dark for two days, no color change is observed. It is because the carbon dioxide present is utilized in the process of photosynthesis by plants. If the experiment is conducted in presence if the light, the color of bromothymol blue would be yellow due to the presence of carbon dioxide.
PCR technique is your answer
