In a factory there are two machines, which emit sound uniformly in all directions. The machines have individual intensity levels (only one machine on at a time) measured at a certain position P to be 84 dB and 87 dB respectively. When both machines are running simultaneously, what is the combined intensity level (in dB) at this position? . If the machine producing 87 dB is located 3.40 m away from the position P, how much sound power (in watts) is the machine emitting? .

In a factory there are two machines, which emit sound uniformly in all directions. The machines have individual intensity levels (only one machine on at a time) measured at a certain position P to be 84 dB and 87 dB respectively. When both machines are running simultaneously, what is the combined intensity level (in dB) at this position? . If the machine producing 87 dB is located 3.40 m away from the position P, how much sound power (in watts) is the machine emitting? .