Brenda is watching a movie at home but the sound on her television is rather low. She asks her brother to turn up the sound. After he increases the volume only 5 decibels, Brenda says "OK. That's good. Thank you." Brenda's detection of this slight increase in volume demonstrates

just-noticeable difference

Explanation:

Based on the information provide can be said that in this scenario Brenda's detection of this slight increase in volume demonstrates the just-noticeable difference or JND. In the context of psychophysics, this term refers to the amount in which something needs to be changed in order for the individual in question to be able to notice or detect the difference, at least 50% of the time in which they are exposed to it. Which is the what is being demonstrated by Brenda in this scenario.

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