The trajectory of a projectile always the trajectory of a projectile always is a straight line, in the same direction as the initial velocity vector follows a circular path curves downward, below the initial velocity vector at first goes up above the initial velocity vector and then curves down

curves downward, below the initial velocity vector.

Explanation:

Projectile launches are generally divided into two types: the oblique throw and the free fall. The free fall of bodies consists of throwing or abandoning projectiles from a hill or any unevenness that has a height in relation to a frame (usually the ground), while the oblique launch consists of launching a projectile at an angle. any relative to a frame (usually the ground).

Regardless of the type, when reading the paragraph above, we can say that the trajectory of a projectile will always be curved down and below the initial velocity vector.

Explanation:

The trajectoy of a projectile is always a parabola concave down, beacuse it's movement is modeled by

(vertical motiion)

So, we know that quadratic equations are represented by parabolas.

So, the first answer is curves downward.

A simpler reason why it curves down is gravity, this acceleration makes the object to change is direction and velocity.

An important fact is that the inital and final point are at the same level, which means the initial velocity vector and the final velocity vector are equal.

However, notice that a projectile trajectory first moves up the initial vector and then moves down.

So, the second answer is at first goes up above the initial velocity and then curves down. However, it's important to notice that we are referring to the trajectory here, because higher positions of the projectile means a least velocity vector, because gravity is reducing the velocity.

3. dark matter

empty space could also be a simple vacuum