Answer
$W=kf$
Work Step by Step
Recall:
If $y$ varies directly as $x$, then, $y=kx$ where $k$ is the constant of variation.
Since $W$ varies directly as $f$, then, with $k$ as a constant of variation,
$$W=kf$$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.