Correct the following statement by changing the underlined part of the sentence.
In a hexagonal closest packing of identical spheres in two layers, one above the other, the coordination number of each sphere will be `ul(12)`.

Explanation

To correct the statement regarding the coordination number of spheres in hexagonal closest packing (HCP), we need to analyze the arrangement of the spheres in the structure.

### Step-by-Step Solution:

1. **Understanding Hexagonal Closest Packing (HCP)**:
- In HCP, the spheres are arranged in a way that maximizes the packing efficiency. The arrangement consists of two layers of spheres, where the second layer fits into the gaps of the first layer.

2. **Identifying Coordination Number**:
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