Answer:
6.32 m
Explanation:
Intensity of sound (I) is inversely proportional the distance to the source (d).
In decibels,
[tex]\Delta \beta=10log\frac{I_1}{I_2}=10 log\frac{d_2^2}{d_1^2}\\\\\Rightarrow 79-69=10 log\frac{d_2^2}{2^2}\\\Rightarrow 10 = 10 log\frac{d_2^2}{4}\\ \Rightarrow d_2^2=4\times 10\\\Rightarrow d_2=6.32 m[/tex]