Please answer ALL PARTS and show your work.

At t = 0, a time-dependent electric field is applied to a hydrogen atom that is in its ground state. Find the probability that the atom will be in the 2p state as t > 00 for a) E = E0 6HT cos(wgt) and b) E = Eu e't/T sin(w0t) In both cases you may assume that E0 is sufficiently small so that first-order perturbation may be applied, and sufficiently coherent so that it can be treated as a classical field