White light is used in a YDSE with `D = 1 m` and `d = 0.9 mm`. Light reaching the screen at position `y = 1 mm` us passed through a prism and its spectrum is obtained. Find the missing lines in the visible region of this spectrum.

Explanation

To solve the problem step by step, we will follow the outlined procedure to find the missing lines in the visible spectrum produced by the Young's Double Slit Experiment (YDSE) using white light.

### Step 1: Understand the Given Values
We have the following values:
- Distance to the screen \( D = 1 \, \text{m} \)
- Slit separation \( d = 0.9 \, \text{mm} = 0.9 \times 10^{-3} \, \text{m} \)
- Position on the screen \( y = 1 \, \text{mm} = 1 \times 10^{-3} \, \text{m} \)

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