This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Example Input: Passage: Naturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or ancient Egypt. The earliest known glass objects, of the mid third millennium BCE, were beads, perhaps initially created as accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing. Question: What was obsidian used to make in prehistoric times?
Example Output: cutting tools

Example Input: Passage: Miami is the southern terminus of Amtrak's Atlantic Coast services, running two lines, the Silver Meteor and the Silver Star, both terminating in New York City. The Miami Amtrak Station is located in the suburb of Hialeah near the Tri-Rail/Metrorail Station on NW 79 St and NW 38 Ave. Current construction of the Miami Central Station will move all Amtrak operations from its current out-of-the-way location to a centralized location with Metrorail, MIA Mover, Tri-Rail, Miami International Airport, and the Miami Intermodal Center all within the same station closer to Downtown. The station was expected to be completed by 2012, but experienced several delays and was later expected to be completed in late 2014, again pushed back to early 2015. Question: In what year was the Miami Central Station originally supposed to have been completed?
Example Output: 2012

Example Input: Passage: The third generation began including a 30-pin dock connector, allowing for FireWire or USB connectivity. This provided better compatibility with non-Apple machines, as most of them did not have FireWire ports at the time. Eventually Apple began shipping iPods with USB cables instead of FireWire, although the latter was available separately. As of the first-generation iPod Nano and the fifth-generation iPod Classic, Apple discontinued using FireWire for data transfer (while still allowing for use of FireWire to charge the device) in an attempt to reduce cost and form factor. As of the second-generation iPod Touch and the fourth-generation iPod Nano, FireWire charging ability has been removed. The second-, third-, and fourth-generation iPod Shuffle uses a single 3.5 mm minijack phone connector which acts as both a headphone jack and a data port for the dock. Question: Which model of iPod combined the headphone jack and data port?
Example Output:
Shuffle