Tolong ya pakai cara

No.1
½ × (6+4) × 8 = 40 cm²

no.2
(11+19) × 4 ÷ 2 = 60 cm²

no.3
a. L ⬜ = 4 × 12 = 48 cm²
b. L trapesium = (10+12) × 5 ÷ 2 = 55 cm²
55 + 48 = 103 cm²

semoga membantu ^^