How to upload new file versions and restore old version on Google Drive

support.google.com/a/users/an...
Upload a new version of a non-Google file to Drive:
On the web
In Drive, right-click the file that isn’t in a Google format and select Manage versions.
Click Upload New Version and select the file from your computer.
When the new version is uploaded, click Close.
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Download or revert to earlier versions of non-Google files in Drive:
In Drive, click the file and at the top right, click More Manage versions.
Click More Download to download the file.
(Optional) To revert to an earlier version (such as the one you downloaded above), click Upload New Version, find the version of the file, and click Open.
Click Close.