show that the lifetime of the 2P state of atomic hydrogen is approximately 1.6ns. For your conviencr, the radial functions R21 and R10 as well as the ionisation frequency (omega) and the relationship lifetime = 1/ A (where the A represents Einstein's Coefficient for spontaneous emission, have been supplied. Please show all working with a clear explanation of how the A value is obtained.

2P State of Hydrogen W = 2 . 067 x 1016 HZ 3/2 2 r -r / 20 0 R 21 13 2 90 e 3/ 2 -r/do R 10 a 2 e Azp