During a fire drill in your dormitory, you notice that the sound waves from the two alarms on your floor interfere with each other; you hear five beats every two seconds.

(a) If the average of the two frequencies is \(3500 \mathrm{~Hz}\), what are the frequencies of the two alarms?

(b) If your room is \(15 \mathrm{~m}\) from each alarm, what is the intensity \(I\) of the sound if the power output is \(60 \mathrm{~W}\) for each alarm?