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'.

[Q]: Context: He first spent over a year in Mexico, where he was diagnosed with tuberculosis Link Information: Mexico ( ; ), officially the United Mexican States (UMS; , ), is a country in the southern portion of North America Question: In which continent was Horiguchi diagnosed with tuberculosis?
[A]: Answer: North America


[Q]: Context: the Japanese government again dispatched Un'yō in September 1875 under the command of Inoue Yoshika to provoke a military response Link Information: none Question: How long did Yoshika command Un'yō?
[A]: Answer: none


[Q]: Context: Walsh first developed what would become the West Coast offense when he was offensive coordinator of the Cincinnati Bengals, working under legendary head coach Paul Brown. However, Walsh truly perfected this strategy as the head coach of the San Francisco 49ers. Link Information: The team was led in its turnaround from late 1970s doormat by new owner Edward J. DeBartolo Jr. and head coach Bill Walsh. Question: How many years was Walsh the head coach of the team he went to after the Bengals?
[A]:
Answer: 18