Answer:
ST = 7.1 in
Explanation:
we can use SOH-CAH-TOA because we've got a right triangle
side ST would be 'adjacent'
side TU would be the 'hypotenuse'
so we use Cosine because that's used when you're dealing with adjacent and hypotenuse:
cos 42° = ST/9.5
ST = cos 42° × 9.5
ST = 7.1