What is the final elevation if a bird starts at 20 m and changes 16 m

36 meters.

Step-by-step explanation:

We are asked to find the final elevation of a bird that starts at 20 m and changes 16 m.  

Since the bird's initial elevation is 20 m and it changed 16 m in positive direction, so bird's final elevation will be:  

Therefore, bird's final elevation will be 36 m.