what is the relationship between the horizontal range and the impact height of a projectile ie the projectile is landing below the level it was fired at.. i need and equational relationship... any answers that give a link will be reported

Consider two less-than-desirable options. in the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. in the second option you are driving 30 mph and crash head-on into a stationary brick wall. in neither case does your car bounce off the thing it hits, and the collision time is the same in both cases. which of these two situations would result in the greatest impact force?