The commission, and each commissioner, and each officer or other person duly authorized by the commission, shall have the right, at any time, to inspect the accounts, books, papers, and documents of any public utility. The commission, each commissioner, any officer of the commission, or any employee authorized to administer oaths shall have the power to examine, under oath, any officer, agent, or employee of any public utility in relation to the business and affairs of such public utility.