a. 648 cm2 b. 684 cm2 c. 864 cm2 d. 867 cm2

luas ABCD = p xl
162 = 18 x l
l = 162/8
l = 9 cm

BC = 9cm

luas ABFE = pxl
180 = 18 x l
l = 180/18
l = 10 cm

BF = 10 cm

luas BCFG = BC xBF
= 9 x 10 = 90 cm²

Luas permukaan balok =
(2 x 180) + (2x162) + (2x 90)
= 360 + 324 + 180
= 864 cm²

C. 864 cm²