See solution in other versions of Excel:
Question: How do I change the width of a column in Microsoft Excel 2003/XP/2000/97?
Answer: Select the entire column that you wish to modify.
Right-click and select "Column Width" from the popup menu.
When the Column Width window appears, select the new width value for the column and click on the OK button.
Now the selected column should reflect this new width.
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