Answer:
Explanation:
The double slit interference phonemene is described for the case of constructive interference
           d sin θ= m λ                   (1)
let's use trigonometry to find the sinus
         tan θ = y / L
in general in interference phenomena the angles are small
        tan θ = sin θ / cos θ = sin θ
  
The double slit interference phonemene is described for the case of constructive interference
           d sin θ = m lam                    (1)
let's use trigonometry to find the sinus
         tan θ = y / L
in general in interference phenomena the angles are small
        tan θ = sin θ / cos θ = sin θ
we substitute
       sin θ = y / L
we substitute in equation 1
          d y / L = m λ
          λ = dy / L m
let's reduce the magnitudes to the SI system
   d = 0.44 mm = 0.44 10⁻³ m
   y = 5.5 mm = 5.5 10⁻³ m
   L = 4.2m
   m = 1
let's calculate
         λ = 0.44  10⁻³ 5.5 10⁻³ / (4.2 1)
          
         λ = 5.76190 10-7 m
let's reduce to num
   lam = 5.56190 10-7 m (109 nm / 1m)
   lam = 556,190 nmtea
we substitute
       without tea = y / L
we substitute in equation 1
          d y / L = m lam
          lam = dy / L m
let's reduce the magnitudes to the SI system
   d = 0.44 me = 0.44 10-3 m
   y = 5.5 mm = 5.5 10-3
   L = 4.2m
   m = 1
let's calculate
         lam = 0.44 10⁻³  5.5 10⁻³ / (4.2 1)
          
         lam = 5.76190 10⁻⁷ m
let's reduce to num
   lam = 5.56190 10⁻⁷ m (109 nm / 1m)
   lam = 556,190 nm