Earth curvature

Question

Because of earths curvature, a person can see a limited distance to the horizon, and the higher the location of the person, the farthest the person can see, so the distance D in miles to the horizon can be estimated by D (h) =1.22^h, where h is the height of the person above the ground in feet, so how high does a person have to be to see 16 miles?

Answer 1

D(h)=1.22^h, so when D=16 miles, 1.22^h=16, hlog(1.22)=log(16), h=log(16)/log(1.22)=13.94 feet. (The logarithmic base is arbitrary as long as the same base is applied to both numerator and denominator.)