Correct! Their intensity.

80 = 10 log (I/10-12)
log (I/10-12) = 8
I/10-12 = 1X108
I = 1X10-4 W/m2

For 3 speakers:
3I = 3X1X10-4 = 3X10-4 W/m2
IL = 10 log (3X10-4/10-12)
= 10 log 3X108 =10 X 8.48 = 85 db

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