Answer: Choice B
Step-by-step explanation:
You divide the opposite side over the hypotenuse to compute the sine ratio of the angle. If angle Y is the reference angle, then side XZ = 7.4 is the opposite side and YZ = 10.9 is the hypotenuse (always opposite the 90 degree angle).
Therefore,
sin(Y) = opposite/hypotenuse
sin(Y) = 7.4/10.9
sin(Y) = 0.678899
sin(Y) = 0.68