Formulas & Q1 Reading 14

Does anyone have a sheet/file with a list of all the formulas? Similarly, does anyone know whether we have be able to use the formulas of Reading 15 on Taxes & Private Wealth Mgt? Finally, on the first question of Reading 14 about Christa’s return requirement, the answer key states that the nominal return is 7.4% and her required real return is 4.5%. Why would the latter be a real return and not a nominal return given that nothing has changed other than that she reduces her monthly expenses by combining apartment and studio. She basically reduces her monthly costs and hence needs a lower nominal return on her investment portfolio.

Just forget about my question on Reading 14; I misinterpreted the question and the answer key makes sense. Any comments on the formulas would be very much appreciated though.