Answer
$US = 1.280$
Work Step by Step
$\frac{US}{OS} = tan ~52^{\circ}$
$US = (OS) ~tan ~52^{\circ}$
$US = (1) ~tan ~52^{\circ}$
$US = 1.280$
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.