Answer:
1.5 above sea level goes in between 1 and 2, at 1.5.
The absolute value of -4.5 is 4.5, so it goes in between positive 4 and 5 at 4.5.
-2 is just that, negative 2. It goes on -2.
The opposite of 4 is negative 4, so it goes on -4.
Th absolute value of 1 is 1, so it goes on 1.
2.5 below sea level would go at -2.5.
-(-3) would be positive 3, so it goes on 3.
-3.5 is just that, negative 3.5, so it goes on -3.5.
The opposite of -5 is positive 5, so it goes on 5.