The research department of a big insurance company is investigating if a car, Ford model XXI, tips over easier than required safety standards.A sample of 13 crashed Ford XXI has been studied.The study showed that these cars tipped over, on average when speeding 170 Km/h, with the standard deviation of 22 Km/h.But the manufacturing safety standard for the tip over speed is 185 Km/h.

Test if Ford XXI runs statistically higher risk of turn over, at 1% level of significance than the required standard, by answering following questions.

a. Write down the H₁hypothesis.

b.What is the probability distribution of test statistics for this question?

c.Find the critical value for this test. (Use 3 digits after decimal point)

d.Find thetest statisticfor this test. (Use 3 digits after decimal point)

e.Therefore, H₀is