1. **Problem 1: Calculate the angle of elevation of point B from point A.** The boy at point A is 5 m from the building's foot, the bird at point B is 8 m above the ground on top of the building. 2. **Step 1:** Identify the right triangle formed by points A, the foot of building, and B. - Horizontal distance (adjacent side) = 5 m - Vertical distance (opposite side) = 8 m 3. **Step 2:** The angle of elevation $\theta$ is the angle at A between the ground and line AB. By trigonometry, $$\tan \theta = \frac{\text{opposite}}{\text{adjacent}} = \frac{8}{5}$$ 4. **Step 3:** Calculate $\theta$: $$\theta = \tan^{-1} \left( \frac{8}{5} \right)$$ Using a calculator, $$\theta \approx \tan^{-1} (1.6) \approx 58.0^\circ$$ --- 5. **Problem 2: Calculate the total area of the father's land if Pato inherited 19.5 hectares, which is 65% of the total.** 6. **Step 1:** Let total land area be $T$ hectares. The problem states: $$0.65 \times T = 19.5$$ 7. **Step 2:** Solve for $T$: $$T = \frac{19.5}{0.65} = 30$$ **Final answers:** - Angle of elevation $\theta \approx 58.0^\circ$ - Total land area $T = 30$ hectares