The “cold startignition time†of an automobile engine is investigated by agasoline manufacturer. The following 8 times (in seconds) wereobtained for a test vehicle:
1.75, 1.92, 2.62,2.35, 3.09, 3.15, 2.53, 1.91
A Construct andinterpret the 95% confidence interval for the population mean startignition time of an automobile engine.
B Test at 0.05significance level whether the population mean start ignition timeis below 2.9 
seconds. Include the hypotheses, the test st atistic,the p-value, test decision 
and conclusion in the context of theproblem.
C. Does the confidenceinterval in the output support your statistical decision?Explain.
D. Construct a NormalProbability Plot of the data. In your opinion, does the graphsupport an assumption of normality? Explain.
E. Perform aShapiro-Wilk test of normality. State hypothesis, p-value andconclusion. Did this support your decision in part (d) based on thenormality plot?
F. What test decisionerror could you have made and provide an explanation of this errorin context of the problem.
G. Include a copy ofyour R-code, test output, and normal probability plot.
