The sine of an angle is the length of the leg farthest away from the angle divided by the length of the hypotenuse.
The length of the leg farthest from angle O is 20, and the length of the hypotenuse is 52. With this information, we find that:
[tex]\sin(\angle O)=\dfrac{20}{52}[/tex]
We can simplify this fraction into:
[tex]=\dfrac{5}{13}[/tex]
That's your answer. Let me know if you need any clarifications, thanks!
~ Padoru
