$$\begin{gathered} Find the numerical value of P:Q, where, \\ P={\left(\frac{x^m}{x^n}\right)}^{m+n-l}\times {\left(\frac{x^n}{x^l}\right)}^{n+l-m}\times {\left(\frac{x^l}{x^m}\right)}^{l+m-n} and \\ Q={\left(x^{\frac{1}{a-b}}\right)}^{\frac{1}{a-c}}\times {\left(x^{\frac{1}{b-c}}\right)}^{\frac{1}{b-a}}\times {\left(x^{\frac{1}{c-a}}\right)}^{\frac{1}{c-b}} where a,b,c are all different. \end{gathered}$$