Answer: The constant of proportinality is 150.
Step-by-step explanation:
The equation of inverse proportion has the following form:
[tex]y=\frac{k}{x}[/tex]
Where "k" is the constant of proportionality.
In this case, you can observe that R is inversely proportional to d², because it has the form of inverse proportion:
[tex]R=\frac{150}{d^2}[/tex]
Therefore, you can identify that the constant of proportionality "k" is:
[tex]k=150[/tex]
