An object is placed at a distant of `1.50` from a screen and a convex lens placed in between produces an image magnified `4`times on the screen .What is the focal length and the position of the lens.

Explanation

To solve the problem step by step, we will use the lens formula and the magnification formula.

### Given:
- Distance from the object to the screen, \( D = 1.5 \, \text{m} \)
- Magnification, \( m = 4 \)

### Step 1: Define Variables
Let:
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