At \( T(K) \), the \( P, V \) and \( u_{\text{rms}} \) of 1 mole of an ideal gas were measured. The following graph is obtained. What is its slope (\( m \))? (x-axis = \( PV \); y-axis = \( u_{\text{rms}}^2 \); \( M \) = Molar mass)