Question

When an electron move from one level to another an amount of energy is dissipated. Give the equation that will enable you to calculate that amount of energy

Answer 1

http://calculator.swiftutors.com/rydberg-equation-calculator.html

That gives you wavelength lambda (L)
L = c T where c = about 3*10^8 m/s speed of light
and T = period
f = frequency = 1
T
so
L = c/f
and you know E = h f

Answer 2

I mean obviously
f = frequency = 1/T