[tex]a)R = 4 \: cm[/tex]
[tex]L=2 \pi R = 2\pi \times 4 = 8\pi[/tex]
[tex]b)R = \frac{6}{\pi} \: cm[/tex]
[tex]L=2\pi R = 2\pi \times \frac{6}{\pi} = 2 \times 6 = 12 [/tex]
[tex]c)R = 0.(4) = \frac{4}{9} \: cm[/tex]
[tex]L=2\pi R = 2\pi \times \frac{4}{9} = \frac{8\pi}{9} [/tex]
[tex]d)R = 3 \frac{2}{3} = \frac{3 \times 3 + 2}{3} = \frac{9 + 2}{3} = \frac{11}{3} \: cm[/tex]
[tex]L=2\pi R = 2\pi \times \frac{11}{3} = \frac{22\pi}{3} [/tex]
