Calculate the frequency `&` energy of a photon of wave length `4000A`.

Explanation

To calculate the frequency and energy of a photon with a wavelength of 4000 Å (angstroms), we can follow these steps:

### Step 1: Convert Wavelength to Meters
The given wavelength is in angstroms. We need to convert it to meters for our calculations.

1 Å = \( 10^{-10} \) meters

Thus,
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