Project #1
Assume that x is the height the tallest mast on a sail boat.
Create a table of mast heights (10, 20, 30, 40, ..., 100)
and how far a boat must sail (longitude/degrees) before the top
of the mast is no longer visible.
Display the angle in degrees, minutes, seconds.
Project #2
Add to the table created in Project #1 how far the boat has sailed
in feet, miles, nautical miles, meters, and/or kilometers.
Remember distance traveled is on the surface of the earth
which is curved.
Project Assumptions and Equations
 the earth is a perfect sphere
 you can see clearly (haze does not effect seeing long distances)
 3959 earth radius in miles
 6371 earth radius in kilometers
 24875.11 earth circumference in miles
 40030.14 earth circumference in kilometers
 you are located on the prime meridian;
you are on the equator looking directly west
(This does not matter with a perfect sphere, but this will help clarify thinking.)
r  radius of the earth
adjacent side of right triangle and angle θ 
x  height of mast 
r + x  hypotenuse of right triangle 
θ  angle
(at the equator it is a measure of east/west longitude)

Note: θ is an acute angles
that is greater than 0° and less than 90°
import numpy as np
hypotenuse = r+x = r/np.cos(θ)
θ = np.arccos(r/(r+x))
Notes:
1. If (y/h) is the cosine of θ, then θ is the arc cosine of (y/h).
2. In Python the angles are measured in radians, not degrees.
45 deg = 0.7854 rad
90 deg = 1.5708 rad
135 deg = 2.3562 rad
180 deg = 3.1416 rad
What is Sine and Cosine