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

SOLUTION: heat exchangers

PROBLEM: How does a chestnut tree form its heartwood?, Context: The term heartwood derives solely from its position and not from any vital importance to the tree. This is evidenced by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change comes slowly. Thin sapwood is characteristic of such species as chestnut, black locust, mulberry, osage-orange, and sassafras, while in maple, ash, hickory, hackberry, beech, and pine, thick sapwood is the rule. Others never form heartwood.

SOLUTION: the change comes slowly

PROBLEM: Roman Curia make up most of the?, Context: Cardinals elevated to the diaconal order are mainly officials of the Roman Curia holding various posts in the church administration. Their number and influence has varied through the years. While historically predominantly Italian the group has become much more internationally diverse in later years. While in 1939 about half were Italian by 1994 the number was reduced to one third. Their influence in the election of the Pope has been considered important, they are better informed and connected than the dislocated cardinals but their level of unity has been varied. Under the 1587 decree of Pope Sixtus V, which fixed the maximum size of the College of Cardinals, there were 14 cardinal deacons. Later the number increased. As late as 1939 almost half of the cardinals were members of the curia. Pius XII reduced this percentage to 24 percent. John XXIII brought it back up to 37 percent but Paul VI brought it down to 27 percent where John Paul II has maintained this ratio.

SOLUTION:
diaconal order