Answer:
Step-by-step explanation:
length (l) = 3 ft
Width (w) = 3 ft
Height (w) = 6 ft
Surface area = 2*( lw + wh + hl)
= 2* (3*3 + 3*6 + 6*3)
= 2*(9 + 18 + 18)
= 2 * 45
= 90 square ft
