Help me pls cause I’m struggling

What’s #16 asking and how do i solve it?

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)

While the change in blank will remain the same during a collision, the force needed to bring an object to a stop can be blank if the time if collision is blank