Answer:
268 cm²
Explanation:
Surface area = (front + back + left side + right side + top + bottom) areas
since pairs of areas are the same (front back, left rigth, top bottom)
Surface area = (2 · front + 2 · left side + 2· top) areas
= 2 · 11 · 4 + 2 · 11 · 6 + 2 · 4 · 6
= 268 cm²