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

Ex Input:
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.

Ex Output:
the change comes slowly


Ex Input:
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 Output:
heat exchangers


Ex Input:
WHat is second mentioned location?, Context: Cork was one of the most rail-oriented cities in Ireland, featuring eight stations at various times. The main route, still much the same today, is from Dublin Heuston. Originally terminating on the city's outskirts at Blackpool, the route now reaches the city centre terminus of Kent Station via Glanmire tunnel. Now a through station, the line through Kent connects the towns of Cobh and Midleton east of the city. This also connected to the seaside town of Youghal, until the 1980s.[citation needed]

Ex Output:
Ireland