In a semicircle, there exist pi radians, whereas a full circle consists of 2pi radians. Since 2pi equals approximately 2*3.14, it results in roughly 6.28 radians in half a circle. The total of 2pi radians corresponds to 360 degrees.
Result:
6.1°; 425.86 m.
Step-by-step breakdown:
The information provided states that the airplane is at an altitude of 5.7 miles above ground level, while the "radius of Earth is about 4000 miles." Thus,
θ = 2 × cos^-1 (a/ (a + b)), where a = 4000 miles, and b = 5.7 miles.
θ = 2 × cos^-1 (4000/ (4000 + 5.7)) = 6.1°.
To calculate the distance in meters:
Change in distance = 6.1° /360° × 2π × 4000 miles = 425.86 meters.
Consequently, BD⌢ measures at 6.1° and the distance corresponding to this section of Earth is 425.86 meters.
