Its my last question.

the following picture shows a golf ball being hit and given an initial velocity of v0. the ball is hit at an unknown angle above the ground. what are two values that are known, even in the absence of all other numbers? (show all work)

We know the acceleration in the y direction is -9.8 m/s² (assuming the ball is on Earth).  We know the acceleration in the x direction is 0 m/s².  And we know the vertical displacement is 0 m.

The answer to your question is:

Explanation:

In parabolic motion, we know that gravity equals 9.81 m/s² and that the final speed is the same as the initial velocity.

 g = 9.81 m/s²

vo = vf