Answer:
The area of the rectangle in the photograph is:
length x breadth = 12 cm x 3 cm = 36 cm²
Since the photograph and the actual bus are proportional, we can express the actual length and breadth of the windscreen as follows, where k is the proportionality constant:
length_actual = k * 12 cm
breadth_actual = k * 3 cm
We can find k by setting the area of the actual windscreen equal to 1.21 m² and the area of the rectangle in the photo equal to 36 cm²:
1.21 m² = (100 cm)² * k²
k = √(1.21 m² / (100 cm)²) = 0.11
Now we can find the actual length and breadth of the windscreen:
length_actual = k * 12 cm = 0.11 * 12 cm = 1.32 m
breadth_actual = k * 3 cm = 0.11 * 3 cm = 0.33 m
Therefore, the actual length and breadth of the windscreen are 1.32 meters and 0.33 meters, respectively.