 
 <prompt> "Which properties of gas fit affect the efficiency of a filament? Given the previous question, write a context wey contain the answer. E fit be 1 - 20 sentences. Context:" <response>: ```While inert gas dey reduce filament evaporation, e dey also conduct heat from the filament, so e dey cool the filament and reduce efficiency. At constant pressure and temperature, the thermal conductivity of a gas dey depend on the molecular weight of the gas and the cross sectional area of the gas molecules. Higher molecular weight gasses get lower thermal conductivity, because both the molecular weight dey higher and the cross sectional area dey higher. Xenon gas dey improve efficiency because of its high molecular weight, but e dey also cost pass, so dem dey limit e use to smaller lamps.``` 