Sixteen cars are rst driven with a standard fuel and then with Petrocoal, a gasolin with a methanol additive. The results of the nitrous oxide...

Sixteen cars are rst driven with a standard fuel and then with Petrocoal, a gasolin with amethanol additive. The results of the nitrous oxide emissions (NOx) test are as follows:Type of fuel Average NOx Standard deviation of NOxStandard 1:075 0:5796Petrocoal 1:159 0:6134Source: Micheal O. Finkelstein and Bruce Levin, Statistics for Lawyers,Spring-Verlag, New York, 1990, p.230.a. How would you test the hypothesis that the two population means are the same?