Two mischievous children drop water balloons from a bridge as depicted in Figure P3.87. Each water balloon is approximately 30 cm in diameter, and in this figure the red balloon is about 1.8 m below the railing of the bridge. What is the time interval between when the first balloon was let go and the second balloon was dropped? Assume both balloons were let go just above the bridge railing. Take measurements directly from the figure and scale appropriately.

Figure P3.87