A lookout tower above a canyon is 4 meters above ground level. The depth of the canyon is 16 meters below ground level. If 0 represents ground level, which number sentence correctly compares their distances above and below ground level?
level ground
we need to take a level as a reference , our reference level will be the ground,
up will be positive and down will be negative, as the y-axis
so, check every level
the lookout tower is 4 meters above the ground level , it is
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The depth of the canyon is 16 meters below ground level, it is
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