Answer:
Internal sources of data can the salaries and wages of previous subordinate with an equal experience in the same field. The salaries of other subordinates with higher experience and its salary can be used to set the benchmark that what the salary offer must be to the employee. On the other hand, external sources of data includes jobs applications like linked-In, etc, which can help in understanding what are the average salaries or wages in the market for an equivalent experience subordinate. Increase in salaries must compensate inflation increases and experience of work. This means that the inflation in the country can be found by just online search.
