$2.$ The human resources department keeps records on all employees in a company. Here is the information HR keeps in one of its data files: employee identification number, last name, first name, middle initial, department, number of years with the company, salary, education $($coded as high school, some college, or college degree$)$ and age.

a$.$ What are the cases for this data set?

b$.$ Do you think that the variable last name can be treated as a label? Explain your answer.

c$.$ Describe each type of information as a label a quantitative variable or a categorical variable.

d$.$ Set up the spreadsheet that could be used to record the data. Give appropriate column headings and $5$ sample cases.