Question 761886
This problem has already been solved - problem number 761857.

Circumference of tower = 10 m

So radius of tower = {{{10/(2*pi) = 5/pi}}}

Radius of the external fence is 2 more than the radius of the tower

So radius of fence = {{{5/pi + 2 = (5 + 2*pi)/pi}}}

Length of the fence = circumference of the fence = 2*pi*radius

= {{{2*pi*(5+2*pi)/pi}}}

={{{10 + 4*pi}}} = {{{10 + 4*3.14}}} = {{{highlight(22.56)}}} meters approx.

:)