To view previous versions:

Click File > View Version History.

1. A menu opens up and it lists the older versions of the spreadsheet.     

2. Click the checkbox near Highlight Changes to observe the modifications between two different versions of the spreadsheet. 

3. Find versions faster by filtering them out. Click on the settings icon on the top of the version panel and select the desired list of versions..

4. Simply click on a version to preview it on the spreadsheet at left. 

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