Two Brands of Flares - Brand 1 and Brand 2 $\bar { x } _ { 1 }$

Two brands of flares - Brand 1 and Brand 2 - are tested for their burning times (in minutes) .A random sample of 40 of each brand of flare are burned and timed.In order to compute a bootstrap confidence interval for the difference in population means,400 subsequent bootstrap samples were taken and the resulting values of $\bar { x } _ { 1 }$ *- $\bar { x } _ { 2 }$ * were ordered from lowest to highest.The first 10 and last 10 ordered values of $\bar { x } _ { 1 }$ *- $\bar { x } _ { 2 }$ * are given below: First 10: -0.8,-0.1,0.4,0.9,1.2,1.3,1.5,1.6,1.7,1.8
Last 10: 5.1,5.5,5.9,6.1,6.3,6.8,7.0,7.5,8.1,8.8
Use the percentile method to compute a 95% bootstrap confidence interval for the true difference in the average burning time (Brand 1 - Brand 2) .

A) (0.4,7.5)
B) (1.3,6.3)
C) (1.2,6.8)
D) (1.8,5.1)
E) (0.4,8.1)