[填空题]
A standard cylinder of oxygen used i:3(i+8pt q qvay ,posbn a hospital has gauge pressu+7 vg,q 7ykzsure = 2000 psi (13u+qz7 g,kv7y s,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$ hour