The Political Noise Problem. The amount of background

noise is important to television news reporters.
One station developed the formula N = -r^ + 12t + 54
showing the noise level in decibels (N) as it relates to the
time after the speaker stops talking in seconds (t). How
many seconds after the speaker stops will the noise level
be the greatest? Write and tell how you decided.

Your noise equation makes no sense.

You need to define what "r" is and what the exponent is following the ^ symbol.