TASK DEFINITION: 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.
PROBLEM: 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: Who is the President of Nigeria?

SOLUTION: Goodluck Jonathan

PROBLEM: Passage: Modern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further conversion of the DC to 3-phase AC (using power electronics). Thus both systems are faced with the same task: converting and transporting high-voltage AC from the power grid to low-voltage DC in the locomotive. Where should this conversion take place and at what voltage and current (AC or DC) should the power flow to the locomotive? And how does all this relate to energy-efficiency? Both the transmission and conversion of electric energy involve losses: ohmic losses in wires and power electronics, magnetic field losses in transformers and smoothing reactors (inductors). Power conversion for a DC system takes place mainly in a railway substation where large, heavy, and more efficient hardware can be used as compared to an AC system where conversion takes place aboard the locomotive where space is limited and losses are significantly higher. Also, the energy used to blow air to cool transformers, power electronics (including rectifiers), and other conversion hardware must be accounted for. Question: What nowdays electrification systems can use?

SOLUTION: DC motors which directly use the DC or they may be 3-phase AC motors

PROBLEM: Passage: A fleet carrier is intended to operate with the main fleet and usually provides an offensive capability. These are the largest carriers capable of fast speeds. By comparison, escort carriers were developed to provide defense for convoys of ships. They were smaller and slower with lower numbers of aircraft carried. Most were built from mercantile hulls or, in the case of merchant aircraft carriers, were bulk cargo ships with a flight deck added on top. Light aircraft carriers were carriers that were fast enough to operate with the fleet but of smaller size with reduced aircraft capacity. Soviet aircraft carriers now in use by Russia are actually called heavy aviation cruisers, these ships while sized in the range of large fleet carriers were designed to deploy alone or with escorts and provide both strong defensive weaponry and heavy offensive missiles equivalent to a guided missile cruiser in addition to supporting fighters and helicopters. Question: What capability does a fleet carrier offer?

SOLUTION:
offensive