[填空题]
A standard cylinder of oxyge76s.0u h7rbwy56 4biwpvbcw on used in a hospital has gauge pressu1fuupa 2ve ,6ph(y0k )*ahsdwre = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.*pfu0 1de uh6 vkw)y(2phaas ,4 L/min. $\approx$ hour