Answer:
The answer to the first question is -12. The answer to the second question is 28. The answer to the third question is 16 meters apart.
Step-by-step explanation:
If the fish is 12 meters below sea level, its elevation is -12. If the sea bird is 28 meters above sea level, its elevation is 28. If the bird is directly above the fish, they are 16 meters apart because if you subtract 12 from 28 you get 16. I hope this helps you, have a wonderful day! :D