Final answer:
The velocity in the y-direction of an arrow at the highest point of its trajectory is zero meters per second (0 m/s), as it has momentarily stopped moving upwards.
Step-by-step explanation:
The question asks about the vertical component of velocity at the highest point of an arrow's trajectory when shot at an angle. When an object is at the highest point of its projectile motion, its vertical velocity (velocity in the y-direction) is zero because it has momentarily stopped moving upwards before it starts to fall back down due to gravity. Therefore, regardless of the initial velocity or angle of release, the velocity in the y-direction at the highest point will always be zero meters per second (0 m/s).