Answer:
341 cm²
Step-by-step explanation:
Formula :
Surface area = Area of 4 triangle faces + Area of square base
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Solving :
⇒ Surface area = 4 × 1/2 × 11 × 10 + 11²
⇒ Surface area = 2 × 110 + 121
⇒ Surface area = 220 + 121
⇒ Surface area = 341 cm²