As mentioned in the task 1

As mentioned in the task 1.1, the secondary data can be collected in many ways such as, Sales Report, Financial reports, Customer details, like name, age, contact details, etc., Company information, Reports and feedback from a dealer, retailer, and distributor, Management information system, Government censuses, like the population census, agriculture census, etc., Information from other government departments, like social security, tax records, etc., Business journals, Social Books, Business magazines, Libraries, Internet, where wide knowledge about different areas is easily available.
Out of these methods, it is more reliable for a researcher to gather information by using internal sources. Such as sales report, annual reports, customer feedbacks, supplier feedbacks etc. it is because, by using these methods to collect secondary data, has the most recent data which can be used to do an effective research.
Out of these methods, the financial reports of an organization or any institution which researcher use to do a research on can be the best method to collect secondary data