instruction:
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.
question:
Passage: However, early Christian writers who speak of the shape of the particular gibbet on which Jesus died invariably describe it as having a cross-beam. For instance, the Epistle of Barnabas, which was certainly earlier than 135, and may have been of the 1st century AD, the time when the gospel accounts of the death of Jesus were written, likened it to the letter T (the Greek letter tau, which had the numeric value of 300), and to the position assumed by Moses in Exodus 17:11–12. Justin Martyr (100–165) explicitly says the cross of Christ was of two-beam shape: "That lamb which was commanded to be wholly roasted was a symbol of the suffering of the cross which Christ would undergo. For the lamb, which is roasted, is roasted and dressed up in the form of the cross. For one spit is transfixed right through from the lower parts up to the head, and one across the back, to which are attached the legs of the lamb." Irenaeus, who died around the end of the 2nd century, speaks of the cross as having "five extremities, two in length, two in breadth, and one in the middle, on which [last] the person rests who is fixed by the nails." Question: How many ends did the cross supposedly have?
answer:
five extremities


question:
Passage: Most migrations begin with the birds starting off in a broad front. Often, this front narrows into one or more preferred routes termed flyways. These routes typically follow mountain ranges or coastlines, sometimes rivers, and may take advantage of updrafts and other wind patterns or avoid geographical barriers such as large stretches of open water. The specific routes may be genetically programmed or learned to varying degrees. The routes taken on forward and return migration are often different. A common pattern in North America is clockwise migration, where birds flying North tend to be further West, and flying South tend to shift Eastwards. Question: What obsticals will migrating birds avoid?
answer:
large stretches of open water


question:
Passage: Since 2002, the North East of the country has seen sectarian violence by Boko Haram, an Islamist movement that seeks to abolish the secular system of government and establish Sharia law. Nigerian President Goodluck Jonathan in May 2014 claimed that Boko Haram attacks have left at least 12,000 people dead and 8,000 people crippled. At the same time, neighbouring countries, Benin, Chad, Cameroon and Niger joined Nigeria in a united effort to combat Boko Haram in the aftermath of a world media highlighted kidnapping of 276 schoolgirls and the spread of Boko Haram attacks to these countries. Question: When did Boko Haram become active in Nigeria?
answer:

2002