Most drinking water treatment plants in Canada use chlorine as a disinfectant. The use of chlorine in the treatment of drinking water has virtually eliminated waterborne diseases, because chlorine can kill or inactivate most microorganisms commonly found in water. Ingestion of large amounts of chlorine can, however, be dangerous. A city’s drinking water is considered safe as long as the mean chlorine level is 4.2 mg/l or lower. Chlorine levels in one city are known to follow a normal distribution with standard deviation 0.45 mg/l. A water quality inspector measures the chlorine content in 8 samples of drinking water collected at random locations in the city. The mean chlorine level in these samples is calculated to be 4.4 mg/l. (a) Conduct an appropriate hypothesis test at the 5% level of significance to determine whether there is evidence that the city’s drinking water is unsafe. Show all of your steps and calculations. (b) Provide an interpretation of the P-value of the test.