Answer:
The initial energy level = 6
Explanation:
Photon wavelength is proportional to energy. The wavelength of emitted photons is related to the energy levels of the atom as given by the Rydberg formula:
ₕ₁₂
(1/λ) = Rₕ [(1/n₂²) − (1/n₁²)]
where n₂ = final energy level = 2
n₁ = initial energy level = ?
Rₕ = Rydberg's constant = 1.097 × 10⁷ m⁻¹
λ = wavelength = 410 nm = 410 × 10⁻⁹ m
1/(410 × 10⁻⁹) = (1.097 × 10⁷) [(1/2²) − (1/n₁²)]
0.223 = [(1/4) − (1/n₁²)]
(1/n₁²) = 0.02778
n₁² = 1/0.02778 = 36
n₁ = 6.
$34.75 per month
It is a trick question at the end because it says that anything over 250 kwh is $0.03. Although, you are only calculating for 180 kwh and the monthly charge.
Answer:

Explanation:
= Initial pressure = 
= Initial volume
= Final volume = 
Temperature is the same in the initial and final state
From the ideal gas law we have

The final pressure of the system is
.
Answer:
23.246 metres per second
Explanation:
divide the speed value by 2.237
Given the index of refraction, n and speed of light in the vacuum, c, we can solve for the speed of light in the transparent substance by the equation below.
n = c / v
where v is our unknown.
Substituting the known values,
1.7 = (3 x 10^8 m/s) / v
The value of v is equal to 1.76 x 10^8 m/s.