Aball of mass 0.5kg is released form rest at a height of 30m. how fast is it going when it hits the ground? acceleration due to gravity is g-9.8m/s^2

The atoms in a nickel crystal vibrate as harmonic oscillators with an angular frequency of 2.3 × 1013 rad/s. the mass of a nickel atom is 9.75 × 10-26 kg. what is the difference in energy between adjacent vibrational energy levels of nickel? (h = 6.626 × 10-34 j • s, , 1 ev = 1.60 × 10-19 j)