Final answer:
A 3-D reference in computer spreadsheets allows you to refer to the same cell or range of cells across multiple sheets in the same workbook.
Step-by-step explanation:
A 3-D reference in computer spreadsheets, such as Microsoft Excel, allows you to refer to the same cell or range of cells across multiple sheets in the same workbook. This can be particularly useful when working with large amounts of data that is organized into multiple sheets. To create a 3-D reference, you need to include the sheet name followed by an exclamation mark (!) before specifying the cell or range of cells you want to reference.
For example, if you have three sheets named Sheet1, Sheet2, and Sheet3, and you want to refer to cell A1 in all three sheets, your 3-D reference would be: Sheet1:Sheet3!A1.
It is important to note that the referenced cells must contain the same type of data, such as numbers or formulas, and be located in the same position across all the sheets used in the reference.