Answer:<u> Option D
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Solar panels contain a very expensive element, i.e. silicon. This element is able to convert the solar energy into electric energy. The cost of the solar panel gets expensive because of this rare element. It is found in limited areas of the world. That’s why option D is correct. Coal is not used in solar panel, so option B is incorrect. Neither is wind energy, so option A is also incorrect. Water is also not used for exploiting solar energy, which makes option C a wrong answer.
I believe the answer is this:
DNA replication is called semi-conservative because half of the original double-helix appears in one daughter strand formed in replication if you need any more help then please comment and let me know ok. :)
Answer:
Hope the above picture might help you :)
The answer is federal treaties
