In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[EX Q]: What type of equipment is used with liquid oxygen but not other methods of oxygen storage?, Context: Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds. For reasons of economy, oxygen is often transported in bulk as a liquid in specially insulated tankers, since one liter of liquefied oxygen is equivalent to 840 liters of gaseous oxygen at atmospheric pressure and 20 °C (68 °F). Such tankers are used to refill bulk liquid oxygen storage containers, which stand outside hospitals and other institutions with a need for large volumes of pure oxygen gas. Liquid oxygen is passed through heat exchangers, which convert the cryogenic liquid into gas before it enters the building. Oxygen is also stored and shipped in smaller cylinders containing the compressed gas; a form that is useful in certain portable medical applications and oxy-fuel welding and cutting.
[EX A]: heat exchangers

[EX Q]: What was the employer that used this scheme referred to as?, Context: The importation of slaves was made illegal in 1792. Governor Robert Patton (1802–1807) recommended that the company import Chinese labour to supplement the rural workforce. The coolie labourers arrived in 1810, and their numbers reached 600 by 1818. Many were allowed to stay, and their descendents became integrated into the population. An 1814 census recorded 3,507 people on the island.
[EX A]: the company

[EX Q]: Why would two players sit out of a 4 player match?, Context: Sometimes, poly-sided matches that pit every one for themselves will incorporate tagging rules. Outside of kayfabe, this is done to give wrestlers a break from the action (as these matches tend to go on for long periods of time), and to make the action in the ring easier to choreograph. One of the most mainstream examples of this is the four-corner match, the most common type of match in the WWE before it was replaced with its equivalent fatal four-way; four wrestlers, each for themselves, fight in a match, but only two wrestlers can be in the match at any given time. The other two are positioned in the corner, and tags can be made between any two wrestlers.
[EX A]:
tagging