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.

Input: Consider Input: Passage: Northwestern has several housing options, including both traditional residence halls and residential colleges which gather together students who have a particular intellectual interest in common. Among the residential colleges are the Residential College of Cultural and Community Studies (CCS), Ayers College of Commerce and Industry, Jones Residential College (Arts), and Slivka Residential College (Science and Engineering). Dorms include 1835 Hinman, Bobb-McCulloch, Foster-Walker complex (commonly referred to as Plex), and several more. In Winter 2013, 39% of undergraduates were affiliated with a fraternity or sorority. Northwestern recognizes 21 fraternities and 18 sororities. Question: How many fraternities does Northwestern recognize?

Output: 21


Input: Consider Input: Passage: The Prussian Army, under the terms of the armistice, held a brief victory parade in Paris on 17 February; the city was silent and draped with black and the Germans quickly withdrew. Bismarck honoured the armistice, by allowing train loads of food into Paris and withdrawing Prussian forces to the east of the city, prior to a full withdrawal once France agreed to pay a five billion franc war indemnity. At the same time, Prussian forces were concentrated in the provinces of Alsace and Lorraine. An exodus occurred from Paris as some 200,000 people, predominantly middle-class, went to the countryside. Question: To hounour the armistice, Bismarck allowed train loads of what into Paris?

Output: food


Input: Consider Input: Passage: The noise-based speed is defined as the exposure that will lead to a given signal-to-noise ratio on individual pixels. Two ratios are used, the 40:1 ("excellent image quality") and the 10:1 ("acceptable image quality") ratio. These ratios have been subjectively determined based on a resolution of 70 pixels per cm (178 DPI) when viewed at 25 cm (9.8 inch) distance. The signal-to-noise ratio is defined as the standard deviation of a weighted average of the luminance and color of individual pixels. The noise-based speed is mostly determined by the properties of the sensor and somewhat affected by the noise in the electronic gain and AD converter. Question: How are the two ratios found?


Output: subjectively determined based on a resolution of 70 pixels per cm (178 DPI) when viewed at 25 cm (9.8 inch) distance