To determine which of the 3 core samples is the oldest, look at which sample goes furthest back in time (closest to the tree trunk center, which represents the oldest part of the tree). - **Sample B:** Oldest ring is from **1993** - **Sample C:** Oldest ring is from **1978** - **Sample A:** Oldest ring is from **1980** **Conclusion:** **Core sample C is the oldest**, as it contains rings dating back to 1978, which is earlier than the oldest rings in samples A (1980) and B (1993).

Certainly! Here's a detailed explanation of how to determine which core sample is the oldest based on the image: 1. **Understanding Tree Rings:** - Each ring in a tree core represents one year of growth. - The innermost rings are the oldest, as they were formed when the tree was young. - The outer rings are the most recent, formed just before the sample was taken. 2. **Examining the Core Samples:** - In the image, there are three core samples labeled A, B, and C. - To find the oldest sample, look for the core with the earliest (smallest) year on its innermost ring. 3. **Analyzing Each Sample:** - **Sample A:** The innermost ring is labeled 1980. - **Sample B:** The innermost ring is labeled 1993. - **Sample C:** The innermost ring is labeled 1978. 4. **Comparison:** - The earliest ring among all samples is in **Sample C**, from 1978. - Since 1978 predates the rings in A (1980) and B (1993), Sample C is the oldest. 5. **Conclusion:** - The core sample with the earliest starting point (1978) is the oldest. - Therefore, **Sample C** is the oldest of the three core samples. **Summary:** By comparing the innermost rings of each core sample, we determine that Sample C, starting from 1978, is the oldest because it contains the earliest growth rings, indicating it is from the earliest period in the tree's life.