Answer: 4.speed
Explanation:
In this case, we know that the cart remains at a constant 20km/h.
Now, one could say that "the velocity remains constant, because it always is 20km/h"
But remember that velocity is a vector, so this has a direction, and if the cart is going around a turn, then the direction of motion is changing, which tell us that there is acceleration.
But the module of the velocity, the speed, remains constant at 20km/h.
Then the correct option is 4, speed.
<span>The component most affected by the collisions is vertical. The ball's vertical will either decrease or increase due to the collision. If the velocity is high during the collsion the ball's vertical will likely be higher and if the ball's velocity is low the vertical will be as well.</span>
They correspond due to the fact that certain elements are grouped together based on the number of valence electrons on the outer shell of their electron configuration.
For instance, sulfur (S) has 6 electrons in the outer shell, as it is in the 6th group EXCLUDING transition metals (note, never take these into account, as their charge is always +2; a cation)