ANSWER
C.

EXPLANATION
The given function has range:
-3≤f(t)≤3
This implies that, the amplitude is

The function is symmetric with respect to the origin so this is a sine function.
This function is again reflected in the x-axis, hence
a=-3.
The period of this function is

This implies that, b=3,
hence the equation of the function is

The value of f(19) in the given equation is 55.
<h3>What is the function of a linear equation?</h3>
The function of a linear equation illustrates a straight line graph and for a given set of input into the function, there is usually a specific output.
Given that:
We are to find the f(x) = 19.
So;
f(19) = 3(19) - 2
f(19) = 57 - 2
f(19) = 55
Learn more about the function of a linear equation here:
brainly.com/question/14323743
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