[填空题]
In audio and communicatio8xxe )pw7 8)gux 7o- kkwrw2szns systems, the gain, 6 oxzfy;.yu:p $\beta$ in decibels is defined as
$\beta$ = 10log($\frac{P_{out}}{P_{in}}$)
where $P_{in}$ is the power input to the system and $P_{out}$ is the power output. A particular stereo amplifier puts out 100 W of power for an input of 1 mW. What is its gain in dB? dB
