A machine cuts steel to length for nails. The mean length if a nail is 43 millimetres. There is concern that the settings of the machine producing the nails have changed. To test the claim, 12 nails (n=12) were sampled. The mean of the sample is 41.5 and the standard deviation 1.784.To decide if the sample data support the claim that the mean length is 43 millimetres, state your decision in terms of the null hypothesis. Use a 0.02 level of significance.Use 5 step-procedure for testing a hypothesis.
