Answer:
signal-to-noise ratio
Step-by-step explanation:
The measure which compares level of desired signal to that of the background noise in the system is known is signal-to-noise ratio. Signal-to-noise ratio is the ratio of the signal power to that of noise. It is expressed often on decibels. The ratio which is higher than 1:1, means that there is more signal as compared to noise.
Alicia when talking to Maya has to shout when there is more background noise and has to talk easily when there is no noise is an illustration of signal-to-noise ratio.