Answer:
Save as.
Step-by-step explanation:
A spreadsheet can be defined as a file or document which comprises of cells in a tabulated format (rows and columns) typically used for formatting, arranging, analyzing, storing, calculating and sorting data on computer software applications such as Microsoft Excel.
In this scenario, Nadia wants to make changes to her Excel spreadsheet. She wants to keep her original file with its current file name, and save the changed document as a new file.
Hence, the command Nadia should use is "Save as" of the file options in Microsoft Excel.
Basically, the Save as command would save the updated version of the Excel spreadsheet while keeping the previous version of the spreadsheet.