posted by Loki .
A person standing h feet above sea level can seecd miles to the horizon. The distance r is the radius of the earth = 3963 miles. d is the tangent to the circle forming a right angle to the radius. h + r is the tangent. Solve using Pythagorean theorem and secant-tangent theorem. I don't know if this is important but the question also says mount everest summit reaches 29,035 feet above sea level.