This question involves the concepts of the thin lens formula and focal length.
The image "56.25 cm" from the lens.
The focal length of the lens is the half of the radius of curvature.
- f = focal length = ?
- R = radius of curvature = 50 cm
Now, according to the thin lens formula:
- p = object distance = 45 cm
- q = image distance = ?
q = 56.25 cm
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