Which system is responsible for the transportation of oxygen throughout the system

Anybody wanna ? (picture included? )

On a day when the barometer reads 75.23 cm, a reaction vessel holds 250 ml of ideal gas at 20 celsius. an oil manometer ( ρ= 810 kg/m^3) reads the pressure in the vessel to be 41 cm of oil and below atmospheric pressure. what volume will the gas occupy under s. t.p.?

Gordon is going for a run through the park, but it is cold outside. the low outside temperature could affect his personal safety.