Answer:
PNG
Explanation:
PNG files can shrink to incredibly small sizes - especially images that are simple colours, shapes, or text. This makes it the ideal image file type for Web graphics.
Answer:
I think no...Brainly might not allow unique text's.
Answer:
2.489 dB
Solution:
As per the question:
Power ratio, 
The Equivalent of this power ratio in decibel or dB is calculated by taking the log of the power ratio as below:


Thus the value of the power ration in decibel comes out to be 2.489 dB