please help! (listing BRAINLIST and giving points) :)

Answer:
sin∅ = 12/13
Step-by-step explanation:
use pythagorean theorem to find the missing side
a² + 5² = 13²
a² = 13² - 5²
a² = 169 - 25
a² = 144
a = 12
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Sin∅ = opp/hyp
sin∅ = 12/13