instruction:
In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
question:
Passage: The Hudson Valley Rail Trail is a paved 4-mile (6.4 km) east–west rail trail in the town of Lloyd in Ulster County, New York, stretching from the Hudson River through the hamlet of Highland. The trail was originally part of the Poughkeepsie Bridge Route, a rail corridor that crossed the Hudson via the Poughkeepsie Bridge. Controlled by a variety of railroads throughout the 19th and 20th centuries, the bridge was damaged and became unusable after a 1974 fire. By the 1980s the corridor's then-owner, Conrail, had routed all rail traffic in the region north through Selkirk, and was eager to relieve itself of the bridge and adjoining rights-of-way. In 1984, it sold the entire property for one dollar to a felon who did not maintain it or pay taxes on it. The section of the corridor west of the Hudson was seized by Ulster County in 1991 and transferred to the town of Lloyd.
During the 1990s, a broadband utility seeking to lay fiber optic cable paid the town to pass through the former corridor. The town used part of its payment to pave the route and open it as a public rail trail in 1997. The creation of the trail was supported by a local Rotary club, which built a pavilion along the trail. The pavilion includes a donated antique caboose. While the trail originally ended at Route 44–55, it was extended eastward between 2009 and 2010, intersecting Route 9W and continuing to the Poughkeepsie Bridge. The extension was paid for by stimulus funding.
The bridge, now a pedestrian walkway called Walkway Over the Hudson, connects the trail with the Dutchess Rail Trail to the east, creating a 30-mile (48 km) rail trail system that spans the Hudson. The trail is expected to be extended west, where it will border Route 299. As it passes through Highland, the trail is carried by several bridges, connects to four parking areas, and traverses a wetlands complex. The trail forms part of the proposed Empire State Trail.
answer:
What is the full name of the structure that was damaged and became unusable after a fire in 1974?


question:
Passage: By the 15th century the reach and influence of the Burgundian princes meant that the Low Countries' merchant and banker classes were in the ascendancy. The early to mid-century saw great rises in international trade and domestic wealth, leading to an enormous increase in the demand for art. Artists from the area attracted patronage from the Baltic coast, the north German and Polish regions, the Iberian Peninsula, Italy and the powerful families of England and Scotland. At first, masters had acted as their own dealers, attending fairs where they could also buy frames, panels and pigments. The mid-century saw the development of art dealership as a profession; the activity became purely commercially driven, dominated by the mercantile class.
Burgundian rule created a large class of courtiers and functionaries. Some gained enormous power and commissioned paintings to display their wealth and influence. Civic leaders also commissioned works from major artists, such as Bouts' Justice for Emperor Otto III, van der Weyden's The Justice of Trajan and Herkinbald and David's Justice of Cambyses. Civic commissions were less common and were not as lucrative, but they brought notice to and increased a painter's reputation, as with Memling, whose St John Altarpiece for Bruges' Sint-Janshospitaal brought him additional civic commissions.Wealthy foreign patronage and the development of international trade afforded the established masters the chance to build up workshops with assistants.  Although first-rank painters such as Petrus Christus and Hans Memling found patrons among the local nobility, they catered specifically to the large foreign population in Bruges. Painters not only exported goods but also themselves; foreign princes and nobility, striving to emulate the opulence of the Burgundian court, hired painters away from Bruges.
answer:
What were the name of three paintings civic leaders commissioned from major artists?


question:
Passage: In recent years, several other craters of around the same age as Chicxulub have been discovered, all between latitudes 20°N and 70°N. Examples include the disputed Silverpit crater in the North Sea, and the Boltysh crater in Ukraine. Both are much smaller than Chicxulub, but are likely to have been caused by objects many tens of meters across striking the Earth. This has led to the hypothesis that the Chicxulub impact may have been only one of several impacts that happened nearly at the same time. Another possible crater thought to have been formed at the same time is the larger Shiva crater, though the structure's status as an impact crater is contested.The collision of Comet Shoemaker–Levy 9 with Jupiter in 1994 demonstrated that gravitational interactions can fragment a comet, giving rise to many impacts over a period of a few days if the comet should collide with a planet. Comets undergo gravitational interactions with the gas giants, and similar disruptions and collisions are very likely to have occurred in the past. This scenario may have occurred on Earth at the end of the Cretaceous, though Shiva and the Chicxulub craters might have been formed 300,000 years apart.In late 2006, Ken MacLeod, a geology professor from the University of Missouri, completed an analysis of sediment below the ocean's surface, bolstering the single-impact theory. MacLeod conducted his analysis approximately 4,500 kilometres (2,800 mi) from the Chicxulub crater to control for possible changes in soil composition at the impact site, while still close enough to be affected by the impact. The analysis revealed there was only one layer of impact debris in the sediment, which indicated there was only one impact. Multiple-impact proponents such as Gerta Keller regard the results as "rather hyper-inflated" and do not agree with the conclusion of MacLeod's analysis, arguing that there might only be gaps of hours to days between impacts in a multiple-impact scenario (cf. Shoemaker-Levy 9) which would not leave a detectable gap in deposits.
answer:
What are the names of the two craters that are smaller than Chicxulub?