Motion in a Plane

Ship A is sailing towards north-east with velocity $\mathop v\limits^ \to = 30\mathop i\limits^ \wedge + 50\mathop j\limits^ \wedge$ km/hr where $\mathop i\limits^ \wedge$ points east and $\mathop j\limits^ \wedge$ , north. Ship B is at a distance of 80 km east and 150 km north of Ship A and is sailing towards west at 10 km/hr. A will be at minimum distance from B in :