Orbital period can be calculated as:

T₁ = (2πr₁)/v₁

Where r₁is the radius of the orbit and is given as follows:

Where ε₀ is the absolute permittivity of free space and is given as = 8.854 × 10^-12 N^-1C²m^-2

h is Planck’s constant and is given as 6.64 × 10^-34 Js

e is charge on an electron and is equals to 1.6 × 10^-19C

m is the mass of an electron, and is equals to 9.1 × 10^-31 Kg

substituting the values, we get

⇒

On calculating, we get

T₁ = 15.27 × 10^-16 seconds

For n = 2, we get

⇒

On calculating, we get

T₂ = 1.22 × 10^-15 seconds

For n = 3, we get

⇒

On calculating, we get

T₃ = 4.12 × 10^-15 seconds.