Final answer:
This question involves the concept of relative velocity and requires vectorial addition of velocities to find the net velocity and direction of motion.
Step-by-step explanation:
In this question, we are dealing with the concept of relative velocity. To solve this problem, we need to analyze the motion of the oil tanker and the luxury liner separately.
The luxury liner travels north at a speed of 27 km/hr, while the oil tanker travels west at a speed of 19 km/hr. Since they both pass the same spot, we can consider this spot as the origin.
Using the concept of relative velocity, we can add the velocities of the tanker and liner vectorially to find their net velocity. The magnitude of the net velocity vector will give us the speed and the direction of motion.