Answer:
160 m
Explanation:
The intensity, I, of the sound is inversely proportional to the square of the distance, r, from the source.
Hence,
From the question, 
is half of 
Water boiling is an example of a physical change. The rest are chemical changes.
Hope that helps!!
It is simply called Entropy.
True. These are the characteristics of a social drinker.
<span>When two waves of same frequency travel in a medium simultaneously in the same direction then, due to their superposition, the resultant intensity at any point of the medium is different from the sum of intensities of the two waves. At certain points the intensity of the resultant wave has a large value while at some points it has a very small or zero. This is called wave interference.</span>
