Question

9. A chemical plant is required to maintain ambient sulfur dioxide concentration levels in the working environment atmosphere at an average level of no more than 13.50 g/m?. The results of 20 randomly timed measurements of the sulfur dioxide level produced a mean of 15.42 g/m3 and a standard deviation of 3.51 g/mu. Test if the chemical plant is in violation of the working code. If needed, assume that the ambient sulfur dioxide concentration level is normally distributed. (a) [2 marks] Define the parameter of interest using the correct notation. Then, state the null and alternative hypotheses for this study. (b) (1 mark] Calculate the observed value of the test statistic. State the distribution (and degrees of freedom if needed) it follows. (c) (1 mark] Compute the p-value or provide a range of appropriate values for the p-value. (d) [1 mark] Using the signif level a = 0.01, state your conclusions about if the chemical plant is in violation of the working code.

Answer 1