In this task, you're given a statement, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Context: In the winter of 1915, during the Serbian Army's retreat across Albania to the Greek island of Corfu Link Information: Throughout the journey across the mountains, around 70,000 soldiers and 140,000 civilians froze, starved to death, died of disease or were killed by hostile Albanian tribes between November 1915 and January 1916 Question: How long did the army's retreat to Corfu take?
Answer: 2