Considering the given linear function, variable x represents the number of hours since the bowl was filled.
A linear function is modeled by:
[tex]y = mx + b[/tex]
In which:
In this problem, the number of ounces of water left in the bown after x hours is given by:
y = -0.5x + 4.
Variable x is the input, hence, it represents the number of hours since the bowl was filled.
More can be learned about linear functions at https://brainly.com/question/24808124