Question

why the sky's colour blue?​

Answer 1

Answer:

because you are asking silly question

Answer 2

Answer:

The sky is blue because the air scatters blue light from the sun across the sky to down our eyes.

Nitrogen molecules scatter blue light more than they do the other colours.

So a little bit of blue light bounces around in the sky and then enters our eyes.

That make the sky look blue.

Hope this Helpful