Jigglypuff is going to sing everyone to sleep again, and then draw nasty patterns on their faces! He sings at 50 dB.
Bob does not want to fall asleep right now, so he gives Jigglypuff gum so his sound would not become as loud. Under 20 dB, Jigglypuff can be barely heard by anyone and thus does not make everyone fall asleep.
Every piece of gum decreases the sound 1.2 * 10 ^ -8 W/m^2.
How many pieces of gum are required to make sure that no one falls asleep due to Jigglypuff's song?