A ball is thrown with a speed of 20 m/s at an angle of 40°. Which of the following statements describes the motion of the ball at the top of its trajectory?

Answer 1

You didn't list the statements but here's a stab at what I think they will include:

If the ball is thrown with a speed of 20 m/s at an angle of 40° we can blow up the initial conditions and, using trig, break the velocity into an x component and a y component like this:

At the top of the trajectory, the ball will still be traveling with the same velocity in the x direction since there are no forces in the x direction (ignoring air friction) acting on it. So it will still be traveling at 15.32 m/s in the x or horizontal direction. However, since gravity is acting on it in the y direction, it will slow down as it rises until at the top of its trajectory its vertical velocity is 0.