=PLEASE ANSWER= a) What energy photon is released when an electron transitions from n=4 state to an n=2 state?
b) list all the photons that could possibly be released as an electron moves from the second excited (n=3) state to ground state

22. the top of a cliff is located a distance h above the ground. at a distance h/2 there is a branch that juts out from the side of the cliff, and on this branch a bird's nest is located. two children throw stones at the nest with the same initial speed, one stone straight downward from the top of the cliff and the other stone straight upward from the ground. in the absence of air resistance, which stone hits the nest in the least amount of time?