An albatross is flying 87 m above the surface of the ocean. Directly below the albatross, a sea gull is flying 6 m above sea level. Directly below
the birds is a shark, swimming 23 m below sea level. Determine each of the following. Explain your work for each.
a) The difference in height between the sea gull and the shark.
b) The distance between the heights of the sea gull and the shark.