plisss tolong jawab dan pakai cara.No 30 dan 31

30. Volume balok = 12 × 20 × 32 = 7680
Volume prisma = 20 × 6 / 2 × 32 = 1920
Total volume = 9600 (D)

31. Volume kubus = 6 × 6 × 6 = 216
Volume air = 216 × 7 / 8 =189 (C)

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