I have a Macbook pro and a 4TB external Hard drive. Now I want to use ubuntu and windows10 running on the external hard drive in a manner where I get 3 TB for random storage purposes and 500 GB for Linux and 500 GB.So I want to know whether I can use a single hard drive to load BOTH windows 10 and ubuntu and still 3TB more space for my use... do I have to partition the hard drive into three different parts.. I need to use virtual box where windows and ubuntu are running on the external drive and I should be able to use the remaining space..thanks in advance.

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