What does the title of the article, the hansberry of chicago: they join business
acumen with social vision mean?

Strictly speaking, to have "business acumen" is to have the competency to make a sound judgement or a correct decision in a matter related to business, although, more generally speaking, it could also apply to other subjects. Furthermore, to have "acumen" is to have the keenness, the quickness, and the depth of discernment to understand and deal, practically and successfully, with a situation. Finally, to have social vision can be understood as a way of thinking or acting that seeks, or at least takes into account, the welfare of other fellow citizens, particularly if they are disadvantaged.

Carl and Nannie Hansberry were part of Chicago's prominent business class, and, although they never forgot their humble origins, they decided to move to an affluent area of the city that was restricted to white people. They suffered the threats of their neighbors, but continued to live there, and they even defended their case in court, setting an example of the African Americans' fight for their social rights.

The title of the article, therefore, could suggest that the Hansberrys sought to have a better life and they asserted their right to pursue that goal, using good judgement when faced with the incomprehension of their white neighbors, and speaking on behalf of other African Americans who were also advocating for their social rights.  

a complex sentence consists of an independent clause and one or more dependent clauses.  

to write complex sentences, we must use subordinating conjunctions.  

all the complex sentences begin with a subordinating conjunction and when it occurs, a comma must be place at the end of the dependent clause. on the contrary, if the sentence begins with an independent clause, then no comma is used.

after  

although  

as  

because  

before  

if  

since  

when  

for example,  

after she won the competition, she became very popular.  

although my father was hurt, he continued fighting for his rights.  

as all of you got a ten, you will be able to leave early today.  

before he went to the war, he asked his parents to bless him.  

if it is cold, i won’t go out.  

since you didn’t bring the homework, you will get low grades.  

when it is hot in the town, everyone goes to the beach.