A certain loudspeaker system emits sound isotropically with a frequency of 2000 $\mathrm{Hz}$ and an intensity of 0.960 $\mathrm{mW} / \mathrm{m}^{2}$ at a
distance of 6.10 $\mathrm{m} .$ Assume that there are no reflections. (a) What
is the intensity at 30.0 $\mathrm{m} ?$ At $6.10 \mathrm{m},$ what are (b) the displacement amplitude and (c) the pressure amplitude?