it’s asking for LATERAL surface area btw
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Answer:
Lateral surface area = 826.5 m²
Step-by-step explanation:
Formula to calculate the lateral surface area of the triangular prism,
Lateral surface area of the triangular prism = Perimeter of the triangular base × Height
Perimeter of the triangular base = 6 + 11 + 12
= 29 m²
Height of the prism = 28.5 m
Therefore, lateral surface area of the prism = 29 × 28.5
= 826.5 m²