Answer: Horizon is 35777.64 m away from observation deck.
Explanation:
Since we have given that
Height of tower above ground level = 200 m
Radius of earth = 6400 km
Let R be the radius of earth.
Let the height of observation and
Let d be the distance from observation deck to horizon.
so, it makes a right angle triangle.
![(R+h)^2=R^2+d^2\\\\R^2+h^2+2Rh=R^2+d^2\\\\h^2+2Rh=d^2\\\\200^2+2* 6400000* 200=d^2\\\\40000+1280040000=d^2\\\\1280040000=d^2\\\\√(1280040000)=d\\\\d=35777.64\ km](https://img.qammunity.org/2020/formulas/mathematics/high-school/59enymcfl5rl8ii0n1g5dq6ewkbdc88g24.png)
Hence, horizon is 35777.64 m away from observation deck.