berapa luas permukaan balok jika berukuran: a.8 cmx4 cmx2 cm b.8 cmx3 cmx4cm c.9cmx9cmx6cm d.9cmx8cmx4cm

A. 2×8×4 + 2×8×2 + 2×4×2
64 + 32 + 16 = 112
B. 2×8×3 + 2×8×4 + 2×3×4
48 + 64 + 24 = 136
C. 2×9×9 + 2×9×6 + 2×9×6
162 + 108 + 108 =378
D.2×9×8 + 2×9×4 + 2×8×4
144 + 72 + 64 = 280