Soils develop different horizons due to the amount of weather that is being exposed to each individual layer. What separates one horizon from another is the properties that make up each layer.
I think that since it lives on the ocean floor, at the deepest of the ocean. So anyway, the fin on the Eurypterids is still necessary but not that much, since they live on the ocean floor. Their movements mostly on the ocean floor. So fin would not help them "stick" to the floor. Also there are still gravity acts on the Eurypterids and the feet would help them move faster. Hope this helps.
Answer:
I think the pigment should be chlorophyll
and the product is definitely oxygen and energy
