Weighing in at a little over 210MB, Ubuntu 18.04 provides access to the Ubuntu Terminal, as well as the latest version of command line utilities such as bash, ssh, git, apt and so on.
https://betanews.com/2018/05/16/ubuntu-18-04-lts-microsoft-store/
@pmdci replied : Installing v18.04 does not update (aka replace) the previous install (the “why” is explained on MSDN). So it might be worth uninstalling the previous Ubuntu install by right-clicking on its icon and choosing to uninstall it.
origin - https://www.pipiscrew.com/2018/05/ubuntu-18-04-lts-hits-the-microsoft-store-for-windows-10-users-2/ ubuntu-18-04-lts-hits-the-microsoft-store-for-windows-10-users-2