Answer:
a) 8.18.4.854 cm²
b) 43 m²
c) 18.84 m²
Step-by-step explanation:
All calculations use the approximation π = 3.14.
a) This figure is made up of 2 trapezoids and two half circles.
A = {(28 + 12 + 28) × 15/2 + (28 + 33) × 7/2 + 3.14 × 5.5²} cm²
A = (510 + 213.5 + 94.985) cm²
A = 818.485 cm²
b) This is a rectangle minus 2 circles.
A = {20 × 10 - 2 × 3.14 × 5²} m²
A = (200 - 157) m²
A = 43 m²
c) This is a large circle minus a medium circle plus a small circle.
A = 3.14 × (3 m)² - 3.14 × (2 m)² + 3.14 × (1 m)²
A = 28.26 m² - 12.56 m² + 3.14 m²
A = 18.84 m²