Two gliders of masses \(m_1\) and \(m_2\) move along a horizontal, frictionless air track with constant velocities such that the velocity of their center of mass in the laboratory frame is \(v_{\text{cm}} > 0\). An observer moves along the track at a constant velocity \(u\) relative to the laboratory frame, where \(0 \le u \le v_{\text{cm}}\). As the observer's velocity \(u\) increases from \(0\) to \(v_{\text{cm}}\), how do the magnitude of the total linear momentum of the two-glider system, the relative speed between the two gliders, and the total kinetic energy of the system, all measured in the observer's reference frame, change?