9514 1404 393
Answer:
288 km²
Explanation:
The surface area is the sum of the area of the square base and the area of the four triangular faces.
SA = (10 km)² + 4(1/2)(10 km)(9.4 km) = 288 km²
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The area formulas for a square and a triangle are ...
A = s² . . . . area of a square of edge length s
A = 1/2bh . . . . area of a triangle with base b and height h