An object lies `90cm` in air avove water surface. It is viewed form water nearly normally. Find the apparent height fo the object.

Explanation

To find the apparent height of an object that is 90 cm above the water surface when viewed from the water, we can follow these steps:

### Step 1: Understand the problem
We have an object located 90 cm above the water surface. When viewed from the water, the height appears different due to the refraction of light.

### Step 2: Use the formula for apparent height
The formula for the apparent height (d') of an object when viewed from a different medium is given by:

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