Follow the steps below to format your flash drive on ubuntu.
Step 1: From the image above Click on Disk:
Step 2: Select the flash drive to format (see image below):
Step 3: Click on the settings icon, then format partition(see image below):
Step 4: If you want to format the entire flash drive with all partitions, click on the menu icon at the top right corner and click on Format Disk (see image below):
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