A rock thrown with speed 8.50 m/s and launch angle 30.0° (above the horizontal) travels a horizontal distance of d = 19.0 m before hitting the ground. From what height was the rock thrown? Use the value g = 9.800 m/s² for the free-fall acceleration. A second rock is thrown straight upward with a speed 4.250 m/s. If this rock takes 2.581 s to fall to the ground, from what height I was it released? Express your answer in meters to three significant figures. View Available Hint(s) H = Submit 15. ΑΣΦ BE ? m k