Jawaban:

12. V = 1.386 cm³ ; Luas Permukaan = 758 cm²

13. V = 16.000 cm³

14. Panjang = 20 dm

15. V = 1.896 cm³

Penjelasan dengan langkah-langkah:

Volume Balok = p × l × t

Volume Kubus = s × s × s

Luas Permukaan Balok = 2 × (p × l + p × t + l × t)

12

V = 14 × 9 × 11

= 1.386 cm³

LP = 2 × (14 × 9 + 14 × 11 + 9 × 11)

= 2 × 379

= 758 cm²

13

V = 80 × 10 × 20

= 16.000 cm³

14

p = V / l × t

= 120 / 2 × 3

= 120 / 6

= 20 dm

15

Kubus

V = 10 × 10 × 10

= 1.000 cm³

Balok

V = 16 × 7 × 8

= 896 cm³

Volume Gabungan

= 1.000 + 896

= 1.896 cm³

Maaf Kalau Salah