Reference:PPT slideshttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.95https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.95AppA1-Calculation: please determine how many times of sound power will change (increase or decrease) when noise level from 87.8 dB is decreased to 84.8 dB after you apply an