Setup multiple regression analysis in Excel or .Net program based off equations

Need some help turning equations into Excel formulas and/or .Net code to process some data sets for checking accuracy of amount of fluid in a tank based on fluid height and tank dimensions, and meters on fluid dispensers connected to the tank, and calculate accuracy of those dispenser meters. I can supply further details on request. Please let me know if you could do this in Excel and .Net, or just Excel (or if I need something else).