In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: What is a prerequisite for weight to play a factor in conductivity?, Context: While inert gas reduces filament evaporation, it also conducts heat from the filament, thereby cooling the filament and reducing efficiency. At constant pressure and temperature, the thermal conductivity of a gas depends upon the molecular weight of the gas and the cross sectional area of the gas molecules. Higher molecular weight gasses have lower thermal conductivity, because both the molecular weight is higher and also the cross sectional area is higher. Xenon gas improves efficiency because of its high molecular weight, but is also more expensive, so its use is limited to smaller lamps.

Answer: constant pressure and temperature


Question: How did the pope respond to the request?, Context: Neither John nor the rebel barons seriously attempted to implement the peace accord. The rebel barons suspected that the proposed baronial council would be unacceptable to John and that he would challenge the legality of the charter; they packed the baronial council with their own hardliners and refused to demobilise their forces or surrender London as agreed. Despite his promises to the contrary, John appealed to Innocent for help, observing that the charter compromised the pope's rights under the 1213 agreement that had appointed him John's feudal lord. Innocent obliged; he declared the charter "not only shameful and demeaning, but illegal and unjust" and excommunicated the rebel barons. The failure of the agreement led rapidly to the First Barons' War.

Answer: obliged


Question: Which of the following is not an alternative to rotary stepper motors: linear stepper motors, servomotors, or optical scanners?, Context: Stepper motors were and still are often used in computer printers, optical scanners, and digital photocopiers to move the optical scanning element, the print head carriage (of dot matrix and inkjet printers), and the platen or feed rollers. Likewise, many computer plotters (which since the early 1990s have been replaced with large-format inkjet and laser printers) used rotary stepper motors for pen and platen movement; the typical alternatives here were either linear stepper motors or servomotors with closed-loop analog control systems.

Answer:
optical scanners