To find the length of segment UW, we can use the Pythagorean Theorem in triangle URW:
UW^2 = UR^2 + RW^2
UW^2 = 12^2 + 15.9^2
UW^2 = 144 + 252.81
UW^2 = 396.81
UW = sqrt(396.81)
UW = 19.95
Therefore, the length of segment UW is 19.95.
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