Researchers propose a model to explain variation in phytoplankton cell sizes in a marine environment. They base their model on the idea that smaller cells absorb nutrients more
efficiently. The researchers predict that the mean diameter of phytoplankton cells will
change by 50 micrometers for every 5-kilometer increase in distance from the shore
because of a gradual decrease in nutrient availability. To test their model, the researchers
determine that the phytoplankton cells found closest to shore have a mean diameter of
900 micrometers.
Based on the model, what will be the mean diameter of the phytoplankton cells that are
found 25 kilometers from shore?