Short Answer 
The Ferris wheel completes one full revolution in 12 seconds, reaching a maximum height of 55 yards and a minimum height of 5 yards. The diameter is calculated to be 50 yards, making the radius 25 yards.
Step 1: Understand the Timing of the Ferris Wheel
The Ferris wheel completes one full revolution in a time span of 12 seconds. This means that from the starting height of 30 yards, it returns back to the same height after 12 seconds. Throughout this time, the Ferris wheel reaches various heights which are also recorded in a table.
Step 2: Analyze the Height Measurements
The table provides a series of height measurements at specific times. The maximum height is 55 yards while the minimum height is 5 yards. Key times to note include the Ferris wheel reaching the lowest height at 9 seconds and again at 21 seconds, showing the full cycle of motion.
Step 3: Calculate the Dimensions of the Ferris Wheel
To determine the radius and diameter of the Ferris wheel, use the heights measured. The diameter is calculated by subtracting the lowest height from the highest height, giving a result of 50 yards. Therefore, the radius is half of this diameter, which is 25 yards.