without using excel

Problem \#1 (4/10): Textbook Yee Swian has received an advance of $20,000 on a software program she is writing. She will spend $80,000 this year writing it (consider the money to have been spent at the end of year 1), and then receive $60,000 at the end of the second year. The MARR is 12 percent. (a) What is the IRR for this project? Does the result make sense? (b) What is the precise ERR? (c) What is the approximate ERR