A cut trunk shows 26 concentric rings of spring wood and autum wood in alternate rows. The age of trunk would be

Options

A. 13 years
B. 26 years
C. 52 years
D. 104 years

Answer

To determine the age of the trunk based on the number of concentric rings, follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Rings**:
- The trunk shows 26 concentric rings, which consist of both spring wood and autumn wood. Each year, a tree produces one ring of spring wood and one ring of autumn wood.

2. **Identify the Composition of the Rings**:
- Each year, one ring of spring wood is formed in the spring, followed by one ring of autumn wood in the fall. Therefore, each complete year of growth corresponds to two rings (one of spring wood and one of autumn wood).

3. **Calculate the Number of Years**:
- Since there are 26 rings in total and each year consists of 2 rings (1 spring + 1 autumn), you can calculate the age of the trunk by dividing the total number of rings by 2.
- Calculation:
\[ \text{Age of trunk} = \frac{\text{Total rings}}{2} = \frac{26}{2} = 13 \text{ years} \]

4. **Conclusion**:
- The age of the trunk is 13 years.

### Final Answer:
The age of the trunk would be **13 years**.

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