30 seconds of exposure to \(115 \mathrm{~dB}\) sound can damage your hearing, but a much quieter \(94 \mathrm{~dB}\) may begin to cause damage after 1 hour of continuous exposure. You are going to an outdoor concert, and you'll be standing near a speaker that emits \(50 \mathrm{~W}\) of acoustic power as a spherical wave. What minimum distance should you be from the speaker to keep the sound intensity level below \(94 \mathrm{~dB}\) ?