Mechanics projectile motionWatch
For e) why is the direction 50 degrees "below the horizontal" ?
It looks like it's above
Because the motion of the ball follows a quadratic curve and is therefore symmetrical about a vertical line drawn through the point where the ball is at its maximum height.
Also, the reason for this is because the acceleration is constant. If the acceleration is constant, the velocity is constant assuming no air resistance. Therefore, the journey will be symmetrical. That's why the time, distance, everything is symmetrical - it's all to do with the acceleration.