Question 1943Navigation General

The correct answer is D) Tidal Current Tables. The Tidal Current Tables published by the National Ocean Service (NOS) provide information on the duration and timing of slack water, which is the period of no current flow between the ebb and flood tides. This information is crucial for mariners navigating in tidal waters, as it helps them plan their passage and operations around the slack water periods. The American Practical Navigator, Sailing Directions, and Tide Tables do not specifically contain this level of detail on the duration of slack water.