An automobile manufacturer wants to compare the lifetime of two brands of tire. She obtains a sample of five tires of each brand. On each of five cars, she mounts one tires of each brand on each from...

An automobile manufacturer wants to compare the lifetime of two brands of tire.  She obtains a sample of five tires of each brand.  On each of five cars, she mounts one tires of each brand on each from wheel.  The cars are driven until only 20% of the original tread remains.  The distances, in thousands of miles, for each tire are presented in the following table.

Sample1=Brand A, Sample2=Brand B

Determine if the alternative hypothesis is "right", "left" or "two-tailed" to test that the mean lifetime of Brand B tires is greater than that of Brand A?