Answer:
v_y = v_{oy} - g t
where the upward direction is positive, so the arrow represents this speed (blue) must decrease, reach zero and grow in a negative direction as time progresses
Explanation:
In this exercise you are asked to observe the change in velocity in a projectile launch.
If we assume that the friction force is small, the velocity in the x-axis must be constant
vₓ = v₀ₓ
Therefore, the arrow (red) that represents this movement must not change in magnitude.
In the direction of the y axis, the acceleration of gravity is acting, so the magnitude of the velocity in this axis changes
v_y = v_{oy} - g t
where the upward direction is positive, so the arrow represents this speed (blue) must decrease, reach zero and grow in a negative direction as time progresses
