how to clear space when install spark and "sbt/sbt assembly" not enough space left

there is no space left when ruing "sbt/sbt assembly" , it crazily download things for over two hours
since first time it failed to create directory without sudo, i run second time with sudo

it use up all space, how do i clean for more space or increase space

i am using virtual machine with window 10's Hyper V

originally it has 14GB and only install opencv and now install spark,
but do not know why it use up all,
where are the files? how to clear?