A
using the Cosine rule in ΔSTU
let t = SU, s = TU and u = ST, then
t² = u² + s² - (2us cos T )
substitute the appropriate values into the formula
t² = 5² + 9² - (2 × 5 × 9 × cos68° )
= 25 + 81 - 90cos68°
= 106 - 33.71 = 72.29
⇒ t =
≈ 8.5 in → A
Question 11= B
Question 13= C
I don't know how to do question 12
Ok now that i understand the question better i say it is D
Wouldn't you divide? If so, 5/9 = 0.6
What's your question so I could help?