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How far can you see from the spire Q of a lighthouse ?
A spectator can't see from Q points on the earth's surface which are located "underneath" the touching-point B.
You can calculate the range of vision s based on the earth radius r and the height of the lighthouse h.
Complete the right side of the equation.

bitte warten


  • Click on the light-grey input field. It turns cyan. Enter your solution.
  • You can use the menu aswell which can be opened clicking right.
  • Finish your input by pressing ENTER. Green indicates right, orange false