IS/OR WHY IS IT SO HARD FOR MINORITY WOMEN TO BETTER/OR COMPLETE THEIR EDUCATION?

presumably becase a large percentage of those considered minorities
(and let's remember that minorities has nothing to do with actual
numbers.  Blacks and Asians are considered minorities while Jews
aren't - if Jews were included the statistics would prbably change)
are ipso facto from a low income background where the cost of
education is prohibitive.  and of course not having an education or a
strong financial network (coming from low income families) backing
them up they have to work - usually at minimum wage jobs which drain
their time away without providing them with income to more than
survive.
And of course the patriarchal nature of society plays into this as
well since women generally earn less in the same jobs as men.  they
also are more often saddled with kids in single parent families and
even when there is a family structure the thinking is usually that the
family is better served by depending financially on the man and
therefore his needs come first.

Good comment!
I think it is also (unfortunately) a matter of the cultural background
of some minorities.  This is no criticism of that.  Even among
majority portions of the population, this is a factor.  It is  -
better: it can be -  difficult for women (and also men) to aspire to
and achieve higher education when their family background does not
place much value on this  (This is not just true in the States, there
is a German song to the effect:  if manual work was good enough for
Dad, it's good enough for me).
But this does not apply to all minorities (in USA).  Some Asian
minorities have a tradition of respect for higher education,
regardless of their personal background.  The Vietnamese "boat
people", who came to the States as refugees, have pushed their
children  (well, some of them have).  I receive lists of scholarship
students to a well known boarding school (prep school) and an Ivy
League college, and it is remarkable how many Asiatic names are on the
lists.
 
To return to your question:  it is a matter of "sociology"; minority
is only a part of that.
Regards, Myoarin