One of the spectral lines of caesium has a wavelength of 456nm. Calculate the frequency of this line.

Explanation

To calculate the frequency of the spectral line of caesium with a wavelength of 456 nm, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Wavelength (\( \lambda \)) = 456 nm
- Speed of light (\( c \)) = \( 3 \times 10^8 \) m/s

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