Hi there!
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We know that the equation for the volume of a pyramid is:
V = 1/3(bh)
We know that:
V = 200 km³
b = 12 × 5 = 60 km²
We can plug these into the equation:
200 = 1/3(60)(h)
Simplify:
200 = 20h
Divide both sides by 20:
200/20 = 20h/20
h = 10 km