Answer:
Due to its high magnification power.
Explanation:
A scientist used a light microscope to view an algal cells because light microscope is able to magnify objects up to about a thousand times. Various cellular organelles, such as nuclei, chloroplasts, and mitochondria etc can also be seen clearly with the help of light microscope so that's why scientist used light microscope to study algal cells.
At least 75% of the history of the earth
The interaction between the biosphere and hydrosphere is that the hydrosphere provides water for the biosphere to function, grow, and live. Animals (biosphere), fish (biosphere) need water (hydrosphere) to live and swim.
Among the northern Andean countries strongly involved in the illegal coca and drug trade, Columbia is now the predominant coca producer, so the answer would be option A.
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