Final answer:
A 3 dB increase in sound intensity leads to the sound being twice as loud, so Genevieve would experience a sound intensity that is twice as loud in comparison to before the increase.
Step-by-step explanation:
When Marguerite turns up the sound on her computer speakers by 3 dB to play her favourite song, the sound intensity doubles. The decibel (dB) scale is logarithmic, not linear, and a change of 3 dB represents a doubling of the sound intensity. Therefore, for Genevieve who is in the next cubicle, the sound would be twice as loud. In terms of energy striking the ear, a 3 dB increase does not lead to the sound being three, five, or exactly as loud as before; rather, it is precisely twice as intense.
To summarize using specific examples, a factor of five in intensity corresponds to a difference of 7 dB in sound intensity level, and a factor of ten in intensity corresponds to 10 dB. So, for a change of 3 dB, the increase in intensity is by a factor of two, which means the sound energy striking Genevieve's eardrum is double.