which of these basic quantities to choose can depend on the physics problems being investigated, and sometimes choosing one thing as a natural unit means that the size of something else does not become used as a natural unit in that system. it is used to make sodas sour. however, japan had lost a huge part of its food resources and the majority of its navy. she was the only female taking the class. they may feel pain in their hand, even though it is not there. smoking is not allowed in any part of the underground. 