Given:
Elevation of Vander's home = -108 feet
Elevation of Gali's home is ⅔ of that depth below sea level.
Thus, the elevation of Gali's home is:
⅔ of -108 feet =

We know that the elevation of Vander's home is already below sea level since it's a negative value.
Therefore, since the elevation of Gali's home is ⅔ of the depth of Vander's home below sea level, the elevation of Gali's home is:
-72 feet
ANSWER:
-72 feet