The model has resulted into a formula called the Rydberg formula. It also came about from the electron transfer within the hydrogen atom. The formula is shown in the picture, where RH is the Rydberg constant and λ is the wavelength . Thus, the solution is as follows:
is the Calcium
because the calcium in group two which group two has 2 electron and also calcium and Potassium 4s sub level group potassium has 1 electron. :)