1. **Problem 1: Area of the shaded region formed by arcs of radius 7 cm at vertices A, B, C, and D of quadrilateral ABCD.** 2. Each arc is a quarter circle with radius $r = 7$ cm. 3. The area of one quarter circle is given by the formula: $$\text{Area}_{\text{quarter circle}} = \frac{1}{4} \pi r^2$$ 4. Calculate the area of one quarter circle: $$\frac{1}{4} \pi (7)^2 = \frac{1}{4} \pi \times 49 = \frac{49\pi}{4}$$ 5. Since there are 4 such arcs, the total area of the shaded region (sum of all quarter circles) is: $$4 \times \frac{49\pi}{4} = 49\pi$$ 6. Therefore, the area of the shaded region is: $$49\pi \approx 49 \times 3.1416 = 153.94 \text{ cm}^2$$ --- 7. **Problem 2: Area of the major sector of a circle with radius 28 cm and central angle 45°.** 8. The formula for the area of a sector is: $$\text{Area}_{\text{sector}} = \frac{\theta}{360} \pi r^2$$ where $\theta$ is the central angle in degrees. 9. Calculate the area of the minor sector (45°): $$\frac{45}{360} \pi (28)^2 = \frac{1}{8} \pi \times 784 = 98\pi$$ 10. The major sector angle is: $$360° - 45° = 315°$$ 11. Calculate the area of the major sector: $$\frac{315}{360} \pi (28)^2 = \frac{7}{8} \pi \times 784 = 686\pi$$ 12. Approximate the area: $$686\pi \approx 686 \times 3.1416 = 2154.37 \text{ cm}^2$$ **Final answers:** - Area of shaded region formed by arcs: $\boxed{49\pi \approx 153.94 \text{ cm}^2}$ - Area of major sector: $\boxed{686\pi \approx 2154.37 \text{ cm}^2}$