We have that every gas satisfies the fundamental gas equation, PV=nRT where P is the Pressure, V is the volume of the gas, n are the moles of the gas, R is a universal constant and T is the Temperature in Kelvin. We have that PV/T=nR and during our process, the moles of the gas do not change (no argon enters or escapes our sample). See attached.
Carbon is not combustible because when it combines with oxygen its energy increases thus it doesnt combust.
Depends on where you live but generally speaking it is either June or July