Detailed Instructions: In this task, you're given a passage, 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: Passage: Bill Johnson was born in Los Angeles, California, on March 30, 1960, and moved with his family to Boise, Idaho, when he was seven. He learned to ski at Bogus Basin in the late 1960s. Two years later, they moved to Brightwood, Oregon, near Mount Hood, and Johnson later attended Sandy Union High School in Sandy. He was a troubled youth who began competitive skiing on nearby Mount Hood as a means of harnessing his energy. After a run-in with the law at age 17, the juvenile defendant was given the choice between six months in jail or attending the Mission Ridge ski academy in central Washington state, and he chose the latter. His talent in the downhill event eventually landed him a spot on the U.S. Ski Team. Johnson made his World Cup debut in February 1983 and finished sixth in the downhill at St. Anton, Austria.
Link Information: The Los Angeles metropolitan area (MSA) is the second-largest metropolitan area in the nation with a population of 13.1 million people. Question: What is the population difference between the two cities Johnson moved between at age seven?
A:
Answer: 12871210