The longest wavelength doublet absorption is observed at `589` and `589.6 nm`. Calculate the frequency of each transition and energy difference between two excited states.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Identify the given wavelengths
We have two wavelengths:
- \( \lambda_1 = 589 \, \text{nm} \)
- \( \lambda_2 = 589.6 \, \text{nm} \)

### Step 2: Convert the wavelengths from nanometers to meters
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