Fires in passenger trains are assumed to occur according to a Poisson process. During the period January 1, 1986 to December 31, 1994, there were 67 fires in passenger trains in Sweden. The total...

Fires in passenger trains are assumed to occur according to a Poisson process. During the period January 1, 1986 to December 31, 1994, there were 67 fires in passenger trains in Sweden. The total distance traveled by passenger trains was 544 × 10⁶
km. Estimate the intensity of passenger train fires (per train km), and construct a two-sided confidence interval with approximate confidence level 95%. You may use the normal approximation.