I think it would be option 4?
Answer:
the wavelength, in nm, of the photon is 487.5 nm
Explanation:
Given:
n = 4 (excited)
n = 2 (relaxes)
Question: Calculate the wavelength, in nm, λ = ?
First, it is important to calculate the energy of the electron when it excited and then when it relaxes.
(excited)
(relaxes)
The change of energy
ΔE = E₁ - E₂=-0.85 - (-3.4) = 2.55 eV = 4.08x10⁻¹⁹J
For a photon, the wavelength emitted

Here
h = Planck's constant = 6.63x10⁻³⁴J s
c = speed of light = 3x10⁸m/s
Substituting values:

Boyle's law p1V1=p2V2
p2=(p1V1)/V2
p2=(205*10^3 Pa * 4*10^-3 m^3 ) / (12*10^-3 m^3)
p2= 68333 Pa
Yes. It is made from baking soda and shaving cream but shaving cream is a constant. You could use things like corn flour instead of baking soda.