Listed below are the lead concentrations in μ​g/g measured in different traditional medicines. Use a 0.01 significance level to test the claim that the mean lead concentration for all such medicines is less than 13 μ​g/g. Assume that the sample is a simple random sample. 5 16 3.5 5 9 22.5 11.5 5 14 9.5
Identify the null and alternative hypotheses.