Answer:
Pressure waves of Sound ; altitude changes
Explanation:
An adequate stimuli is the stimuli a sensory receptor responds to.In the ear, pressure waves of sound is the adequate stimuli.
The hair cells which contain stereo-cilia are the mechanoreceptors. The stereo-cilia bends triggering the opening of ion channels thus transforming the pressure waves of sound into potential s to initiate sensory transduction.
Altitude changes would inappropriately activate sensory receptor.