As she was trying to study, tanisha asked her roommate to lower the radio. her roommate had turned the radio up originally from a volume level of 14 to 15, which was just enough for tanisha to detect. tanisha's roommate turned the radio back down to 14 after tanisha asked her to lower it, which satisfied tanisha. this is probably the result of:

just-noticeable difference

Explanation:

Using principles of psychology and physics, a branch of experimental psychology called psychophysics has been created. This field is focused on the sensation, the sense and the perception of stimuli. Within this branch it has been called just-noticeable difference to the amount that must be changed of some stimulus so that this difference is noticeable, that is to say, the threshold at which the change is perceived.

c.the charges if the proton and electron and gravity