This is the wrong question. If the conditions are sufficient, it is a comprehensive problem of Taoist geometry and algebra. The key point of the problem is that you only give speed in time, distance and speed. To solve this kind of problem, it is generally to draw a plane coordinate, that is, decimal coordinate, and set point A at the origin. The key point of the problem is that you only gave BCD point B three points of direction and speed. I think you have not made the problem clear. According to the title, I'm sure it's because only in this way can the title be partially established. Because you didn't give the distance from point D to point A or its position with point B, I can only determine the direction of D, but not its position, so I can't judge which of the three ports of ACD is closer to point B. The answer I can give you is that if point C is the closest, it is the position of exit C along the direction of 75 degrees east of south. I hope you can read your topic carefully, because you can't solve the problem just by giving a quantity in speed and time!

Under the assumption that your question is wrong, you should at least know the sailing time and the location of point D. To be sure, your question is not a difficult problem, nor a complicated geometric problem, at least two sentences are missing. I hope you can take a closer look.