Some manufacturers claim that non-hybrid sedan cars have a lower mean miles-per-gallon (mpg) than hybrid ones. Suppose that consumers test 278 hybrid sedans and get a mean of 28.5 mpg with a standard deviation of 5.25 mpg. Also, 239non-hybrid sedans get a mean of 26.5mpg with a standard deviation of 8.5 mpg. Suppose that bothpopulationsare known to be normal distributed.

Conduct a hypothesis test to evaluate the manufacturers'claim.Test at a 6% level of significance.

Round your answer to three decimal places

a)Test statistic=

b)p-value =

c) Alpha: