The point P lies at a linear distance 1 m from the corner. Magnetic field due to current in wire Magnetic field due to current in wire. Applying Right hand thumb rule, the magnetic field at P is perpendicular to xy plane and into the plane of drawing (i.e. negative z-direction).
A reference point would be something not on the ship which could be used to calculate distance traveled.
Answer: C.) A lighthouse on a nearby Island
A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.