Mitch and Terry were 0.5 km away from the scenic cliff
Sea level is the base for calculating the depth and the elevation of Earth
It is given that
Total Height of the scenic Cliff = 6.6km
After 1 hour the brothers are at = 6.6 - 1.3 km = 5.3 km from the sea level.
They climb back 0.8 km in the next hour so they will be
5.3 +.8 = 6.1 km from the sea level
6.6 - 6.1 = 0.5 km
Therefore the brothers are 0.5 km away from the scenic cliff
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