#### Answer

1489.1 W

#### Work Step by Step

We know the following equation for the sound intensity level:
$\beta = 10log (\frac{I}{I_0})$
This can be simplified to:
$I = I_010^{.1\beta}$
$I = \frac{10^{.1\beta}}{10^{12}}$
$I =10^{.1\beta-12}$
We know the following equation for the power of a spherical wave:
$I = \frac{P}{4\pi r^2}$
Thus, we should plot I versus $\frac{1}{4\pi r^2}$, where r is the distance in the table.
We now plot these points in excel. Doing this, we find that the trendline, when the y-intercept is set equal to zero, has a slope of 1489.1, which is our value for power.