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: AA gunnery was a difficult business. The problem was of successfully aiming a shell to burst close to its target's future position, with various factors affecting the shells' predicted trajectory. This was called deflection gun-laying, 'off-set' angles for range and elevation were set on the gunsight and updated as their target moved. In this method when the sights were on the target, the barrel was pointed at the target's future position. Range and height of the target determined fuse length. The difficulties increased as aircraft performance improved. Question: What was the problem with AA gunnery?

SOLUTION: successfully aiming a shell to burst close to its target's future position

PROBLEM: Passage: Under the 1963 constitution, Massamba-Débat was elected President for a five-year term. During Massamba-Débat's term in office the regime adopted "scientific socialism" as the country's constitutional ideology. In 1965, Congo established relations with the Soviet Union, the People's Republic of China, North Korea and North Vietnam. Massamba-Débat's regime also invited several hundred Cuban army troops into the country to train his party's militia units and these troops helped his government survive a coup in 1966 led by paratroopers loyal to future President Marien Ngouabi. Nevertheless, Massamba-Débat was unable to reconcile various institutional, tribal and ideological factions within the country and his regime ended abruptly with a bloodless coup d'état in September 1968. Question: What was a term that could describe the political philosophy of the Congo under Massamba-Debat?

SOLUTION: scientific socialism

PROBLEM: Passage: Two Polish friends in Paris were also to play important roles in Chopin's life there. His fellow student at the Warsaw Conservatory, Julian Fontana, had originally tried unsuccessfully to establish himself in England; Albert Grzymała, who in Paris became a wealthy financier and society figure, often acted as Chopin's adviser and "gradually began to fill the role of elder brother in [his] life." Fontana was to become, in the words of Michałowski and Samson, Chopin's "general factotum and copyist". Question: Who is stated as a jack of all trades in service to Frédéric?

SOLUTION:
Julian Fontana