11. Determine the altitude of the triangle

\(ABC\) and \(PQR\) are similar triangles. If the lengths of \(AB\) and \(PQ\) are 7 \(cm\) and 9 \(cm\), respectively. The corresponding altitude of \(\triangle ABC\) is 9 \(cm\), then the corresponding altitude of \(\triangle PQR\) is 13.57112.57110.57111.571 \(cm\).