Similar to Problem 27.19, except the air base is 6940 ft, the flying height above mean sea level is 12,520 ft, the x and y photo coordinates on the left photo are xa = 37.98 mm., ya = 50.45 mm., xb = 24.60 mm., and yb = -42.89 mm, and the x photo coordinates on the right photo are x1a = -52.17 mm and x1b = -63.88 mm.