4 A decibel, , is a unit used for measuring the relative loudness of sounds. Its value is given by the formula = 10 log ( 0) where is the intensity of the sound in watts per square meter and 0 is the intensity threshold of the least audible sound a human can hear. Let 0 = 1012 watts/2 . a) Find the decibel rating for a sound with an intensity of 150 1012 watts/2 . b) Find the decibel rating for a sound with an intensity of 2.3 107 watts/2 . c) Two people are showing off the power of their car stereos. Enrique's stereo is rated at 120 decibels, and his friend's stereo is rated at 115 decibels. Enrique claims that his system is three times as intense as his friends' system, but his friend disagrees because it is only a difference of 5 decibels. Is Enrique's claim accurate? Support your answer with mathematical reasoning