Which button do you click to add up a series of numbers:

🧠 Explanation:

In MS Excel, the AutoSum button, represented by the sigma symbol (Σ), is used to quickly add a series of numbers. Found in the toolbar, it automatically generates a sum formula for selected cells, streamlining calculations. AutoSum is essential for financial, statistical, or data analysis tasks, saving time and reducing errors. Understanding its function enhances Excel proficiency, a critical skill in business, accounting, and data management, ensuring accurate and efficient numerical computations in spreadsheets.