The radius of the completed cone is
... 18×(300°/360°) = 15
The height of the completed cone is found from the Pythagorean theorem:
... 15² + h² = 18²
... h = √99 = 3√11
The volume is given by
... V = (1/3)πr²·h = (1/3)π·15²·3√11
Dividing this value by π gives 225√11 cubic units.
You haven't provided the steps.
mathisfun.com/geometry/construct-linebisect.html
Here is a useful link to the correct steps. The instructions may not be exactly the same but I think you can do it.
T=d/v
540/(230+w)=380/(230-w)
540(230-w)=380(230+w)
124200-540w=87400+380w
124200-920w=87400
-920w=-36800
w=40
So the wind speed is 40 miles per hour.