How Might the middle layer contribute to your understanding of the history of the rock layers? How certain can you be?

The Middle layer has no fossils. As such, the layer is likely not the same age as the fossil above and below it. The middle layer might represent a rock intrusion that occurred at most 445.6 MYA, based on the age of the trilobite. The middle layer could also be older than Peripatus, at least 570 million years ago. The age of the middle layer can’t be stated with any certainty