Question

How global warming is caused ?

Answer 1

Hello,
Here is your answer,

Global warming is caused by human activities such as burning fossil fuels, deforestation and farming.

Hope helps :D

Answer 2

$\huge\textbf{Green House Effect :}$

When sun's radiations entre the earth...these increase the temperature of the earth. As these radiations we're unable to escape. This is known as Green House Effect..
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$\textbf{Causes of Green house effect}$

1) Cutting of trees. (Deforestation)
to make house and for cropping the crops.

2) Increase in population etc. are the causes of green house effect.

* Due to increase in population vehicles are also increasing day by day.... These vehicles release Carbon-dioxide and other harmful gases which goes up in the air and hence cause air pollution. $\textbf{Pollution}$ is also the main cause of increase in green house effect day by day.
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