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: 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: What residential units have revitalized New Haven?, Context: Since approximately 2000, many parts of downtown New Haven have been revitalized, with new restaurants, nightlife, and small retail stores. In particular, the area surrounding the New Haven Green has experienced an influx of apartments and condominiums. In recent years, downtown retail options have increased with the opening of new stores such as Urban Oufitters, J Crew, Origins, American Apparel, Gant Clothing, and an Apple Store, joining older stores such as Barnes & Noble, Cutlers Records, and Raggs Clothing. In addition, downtown's growing residential population will be served by two new supermarkets, a Stop & Shop just outside downtown and Elm City Market located one block from the Green. The recent turnaround of downtown New Haven has received positive press from various periodicals.

SOLUTION: apartments and condominiums

PROBLEM: Small pneumatic __ can hold only one person., Context: A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less robust than in commercial designs with shorter maintenance periods, but safety systems such as locks on shaft access doors, fall arrestors, and emergency phones must still be present in the event of malfunction.

SOLUTION:
elevators