What hypothesis testing procedure should you use to answer these questions?

What hypothesis testing procedure should you use to answer these questions? Assume all samples are simple random samples, and assume α = 0.05 if it isn't specified.

A car company says that the mean gas mileage for its luxury sedan is at least 21 mpg. You believe the claim is incorrect 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 = 0.05, test the company's claim.

Question 20 options:

One sample z-test for the population mean.

Two sample z-test for the population means.

One sample z-test for proportions.

Two sample z-test for proportions.

One sample t-test for the population mean.

None of our hypothesis tests fit.