Answer:
71.75 milliroentgens per hour
Step-by-step explanation:
The intensity(I) of Radiation varies inversely as the square of the distance (D) from the machine.
This is written as:
[tex]I \propto \frac{1}{D^2} \\$Introducing the constant of Variation k$\\I = \frac{k}{D^2} \\$When D=3 meters, I=62.5 milliroentgens per hour$\\62.5= \frac{k}{3^2}\\k=62.5 X 9 =562.5\\$Substituting K=562.5 into the variation equation$\\I = \dfrac{562.5}{D^2} \\$Therefore, When D=2.8 meters$\\Intensity,I = \dfrac{562.5}{2.8^2}=$71.75 milliroentgens per hour$[/tex]
