Noelle stands at the edge of a cliff and drops a rock. the height of the rock is given by the function f(x)-4.9x2 + 15, where c is the number of seconds after noelle releases her rock. cesar, who is standing nearby on the ground, throws a rock straight up in the air. the height of cesar’s rock is given by the function g(x)-4.9x2+10x, where x is the number of seconds after he releases his rock. what is the height the money the two rocks are at the same level above ground.