True dip at a place is `45^@` but dip circle shows an apparent dip of `60^@` . Dip circle is rotated through an angle `90^@` from initial orientation then what apparent dip will be shown by it?

Explanation

To solve the problem, we need to find the apparent dip after the dip circle is rotated through an angle of 90 degrees. We can use the relationship between true dip and apparent dip.

### Step-by-Step Solution:

1. **Identify Given Values:**
- True dip (δ) = 45°
- Apparent dip (δ₁) = 60°

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