Point A is in between points B and C, the distances of B and C from B and C from point A are 1000m and 2000m respectively measured from point A. The angle of elevation of point B is 18°13' while that of C as Ø. The difference in the elevation of B and C is 44.4m. Considering the effects of curvature and refraction, what is the value of Ø? (Note: Assume that point C is higher) where: Earth's Curvature and Atmospheric Refraction Correction (Her): Her(m) = 0.067 K² K (km) = level distance Her K Vertical line Horizontal line Level line