The circular window shown in the diagram has nine panes of equal area. The inner circular pane has radius 20\:cm and the same center, O, as the outer circle. The eight lines separating the outer panes are of equal length, x\:cm, and all, if extended, would pass through O. What is the value of x, to the nearest tenth?
Answer Choices
A. 40.0
B. 36.6
C. 30.0
D. 20.0
E. 43.2