The following are the stopping times of ten cars (in seconds) when braking from 100km/hr:

3.62 3.18 3.29 3.79 3.28 3.24 3.57 3.30 3.91 3.20

a) Compute a 99% confidence interval for the true mean stopping time.

b) Test the claim that the stopping time is less than 3.49 at a significance level of 1%.

[Note: Round off the answer to two decimals.]