Question 35

The Correct Answer is A **Explanation for Option A (one prolonged blast):** According to the U.S. Inland Navigational Rules (specifically Rule 34(d)), a power-driven vessel, when leaving a dock or berth, is required to sound **one prolonged blast** on its whistle. This signal serves as a warning to other vessels approaching the area (such as the fairway or channel) that the vessel is underway and leaving its fixed position. **Why the other options are incorrect:** * **B) four short blasts:** A sequence of four (or more) short blasts is typically used as a danger signal ("I do not understand your intentions or actions," or "I doubt if sufficient passing room exists"). It is not the prescribed signal for leaving a dock or berth. * **C) one long blast:** While the duration of the blast for leaving a dock or berth is *prolonged*, the terminology used in the rules is "prolonged blast" (defined as 4 to 6 seconds). The term "long blast" is generally not the specific terminology used in the context of whistle signals within the rules, and if interpreted differently than "prolonged," it would be incorrect. However, compared to option A, option A uses the exact rule terminology. * **D) no signal is required:** This is incorrect. The Inland Rules explicitly mandate a signal (one prolonged blast) when a power-driven vessel leaves a dock or berth.