No. 11

d = 14 m

r = d/2 = 14/2 = 7 m

t = 10 m

Lp = 2πr(r + t)

Lp = 2 × 22/7 × 7 × (7 + 10)

Lp = 44 × 17

Lp = 748 m² (Opsi: C. 748 m²)

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No. 12

d = 21 cm

r = d/2 = 21/2 = 10,5 cm

Lp = 4 × π × r²

Lp = 4 × 3,14 × (10,5)²

Lp = 4 × 3,14 × 110,25

Lp = 1.384,74 cm² (Opsi: D. 1.384,74 cm²)

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No. 13

Lp = πr(r + s)

Lp = 22/7 × 21 × (21 + 24)

Lp = 66 × 45

Lp = 2.970 cm² (Opsi: B. 2.970 cm²)

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No. 14

V = 1/3 × La × t

V = 1/3 × (AB × BC) × t

V = 1/3 × (18 × 18) × 25

V = 1/3 × 324 × 25

V = 2.700 cm³ (Opsi: C. 2.700 cm³)