Having trouble with a relative motion problem

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Two ships, A and B, are traveling in different directions and speeds, prompting a discussion on calculating their relative motion. The user successfully determined the magnitude and direction of ship A relative to B, as well as the time until they are 150 nautical miles apart. However, they struggle with finding the bearing of ship B relative to A at that time. Suggestions include drawing a vector diagram to visualize the ships' final positions and calculating the difference between those positions. The user contemplates using the time and speeds to find the final positions but remains unclear on the correct approach.
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Two ships, A and B, leave port at the same time. Ship A travels northwest at 20 knots and ship B travels at 27 knots in a direction 43° west of south. (1 knot = 1 nautical mile per hour; see Appendix D.) What are (a) the magnitude (in knots) and (b) direction (measured relative to east) of the velocity of ship A relative to B? (c) After how many hours will the ships be 150 nautical miles apart? (d) What will be the bearing of B (the direction of the position of B) relative to A at that time? (For your angles, takes east to be the positive x-direction, and north of east to be a positive angle. The angles are measured from -180 degrees to 180 degrees. Round your angles to the nearest degree.)

I am able to obtain the answers to a-c, but my textbook is not very helpful on how I'm supposed to find the answer to d.

I get 34.1 knots for a, 83 degrees for b, and 4.4 hours for c. I can't for the life of me figure out how to approach d. Please help!
 
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Draw a picture, you need the vector between the final positions. Think about it, perhaps you are making it hardier then it is.
 
I still don't get it. Are there any other hints you can give me?
 
You need to find the difference between the final positions of the ships.
 
I'm a little confused as to how to get the final positions.

I have the following hunch: If 1 nautical mile per hour = 1 knot, and I know that t = 4.4, couldn't I just add 4.4 knots to each original magnitude and then go from there?
 

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