Respuesta :

[tex]\bf \textit{arc's length}\\\\ s=r\theta ~~ \begin{cases} r=radius\\ \theta =angle~in\\ \qquad degrees\\[-0.5em] \hrulefill\\ r=6\\ \theta = \frac{3\pi }{2} \end{cases}\implies s=6\cdot \cfrac{3\pi }{2}\implies s=9\pi[/tex]

9 is the correct answer