A car company says that the mean gas mileage for its luxury sedan is 21 mpg. You believe the mean gas mileage is lower than this and find that a random sample of 5 cars has a mean gas mileage of 19 mpg and a sample standard deviation of 4 mpg. Assume the gas mileage of all of the company’s luxury sedans is normally distributed. At α = 0.10, use a t-test to assert the validity of the company’s claim.

The alternative hypothesis is:
Question 18 options:

HA: μ < 21

HA: μ > 21

HA: μ = 21

HA: μ ≠ 21