Amissile travels 5000 feet from 50 feet below sea level. what height above sea level is the missile?

Hey there!
Let's think of sea level as 0.
Therefore, anything below sea level is negative, and anything above it would be positive.
If we're starting at -50 and going up +5000, then it's reasonable to think that -50+5000 is going to be out height.
Therefore, the missile is 4950 feet above sea level.
I hope this helps!