Let a function y represent the water level in a harbor measured in meters, and let x represent the number of hours since high tide. At time x is equal to 0 , the water level is 19 point 5 meters (a maximum). At time x is equal to 6 point 2 6 hours, the water level is 10 point 5 meters (a minimum). The period of the function is 12 point 5 hours. After how many hours is the water expected to reach a depth of 17 meters for the first time? Round to the nearest tenth of an hour.