Calculating Distance for Siren Sound Intensity Level

[yaser1989]

Homework Statement

Residents of Hawaii are warned of the approach of a tsunami by sirens mounted on the tops of towers. Suppose a siren produces a sound that has an intensity level of 120 dB at a distance of 2.0m.

Homework Equations

I = P / 4$$\pi$$r$$^{2}$$

The Attempt at a Solution

I calculated I at 2m: I = 1 w/m^2
P at 2m and 1 w/m^2 = 50.26548

I just don't know what values I should use to calculate r.

 

[Redbelly98]

You did not post the actual question.