We know
[tex]\boxed{\sf L=\dfrac{\theta}{360}\times 2πr}[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{135}{360}\times2π(7)[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{27}{72}\times 14π[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{27}{36}\times 14π[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{9}{12}\times 7π[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{63π}{12}[/tex]
[tex]\\ \sf\longmapsto L=\dfrac{21π}{4}in[/tex]
