The dairy industry regulates milk by having inspectors showing up at dairy farms, without warning

The dairy industry regulates milk by having inspectors showing up at dairy farms, without warning. The inspectors take several raw milk samples to check that the raw milk is safe. For example, the inspectors measure the pH level of the raw milk, where raw milk should be 6.7. If the pH level is less than 6.7, it indicates spoilage by bacterial degradation, making the milk acidic and not fit for human consumption. At one farm, the inspector takes one sample of raw milk and finds a pH level of 2.0. The farm is then closed and requested to go through a cleaning process, before being re-tested to decide if they may re-open.

Please answer each of the following, in the context of this question.

a) Describe the "Who" and "What" of the data.

b) Give the value of the statistic and give the value of the parameter?

c) For the sample gathered, briefly describe the sampling error.