In the Excel application, the "MIRR" and "PMT" functions are financial functions. Write a report outlining the concepts, features, and uses of the two financial functions, outlining the process by which people use the function in that part of the company and find a function or method. The problem of financial analysis is similar to the above two functions comparing the strengths and advantages of two functions compared to other ways in the same problem. Take a mathematical example to illustrate each function.