In a growing plant root, the cells at the tip of the root are constantly dividing to allow the root to grow. Because each cell divides independently of the others, a root tip contains cells at different phases of the cell cycle. A scientist wants to determine the average percentage of time that each cell spends in the various phases of the cell cycle based on a 24-hour cycle time. He looks at a section of the onion root and counts the number of cells in each phase of the cell cycle. The table below shows the data he recorded during his observations.