On a number line, the surface of a river is marked at - 225 feet and the top of a building is marked at + 18 feet, where 0 represents sea level. What do - 225 and + 18 represent? 225 feet above sea level and 18 feet below sea level 225 feet below sea level and 18 feet above sea level 225 feet below sea level and 18 feet above 225 225 feet above sea level and 18 feet below 225

Option B.

Step-by-step explanation:

The surface of a river has been marked as (-225) feet and the top of the building at (+18) feet.

If we consider surface sea as a base line to calculate the altitudes of certain place, then altitudes above the the river surface will be positive and the altitudes below the river surface will be negative.

Therefore, (-225) feet of a river means 225 feet below the sea level.

+18 feet of a building means 18 feet above the sea level.

Option B, is the answer.

225 feet below sea level, 18 feet above sea level.

Step-by-step explanation:

Negative represents below, if the 0 is sea level, and positive represents above.