The SAS data set WORK.SALARY, currently ordered by DEPARTMENT, contains 100 observations for each of 5 departments. Which one of the following represents how many observations the WORK.TOTAL data…

The SAS data set WORK.SALARY, currently ordered by DEPARTMENT, contains 100 observations for each of 5 departments. Which one of the following represents how many observations the WORK.TOTAL data set contains? data work.total; set work.salary(keep = department wagerate); by department; if first.department then payroll = 0; payroll + wagerate; if last.department; run;