Berry gordy jr. required all of his acts to endure "charm school" to:

I believe the answer is: carefully control the image of the African American artists.
Berry Gordy Jr. has the ability to spot a musical talent and do proper marketing approach to sell them to the public.
He's known to prmote many african american artists and taught them how to behave and dress in public so they could be acceptable by other ethnicities in the country,

It should be at the center of any map going vertically: the prime meridian, as it passes through greenwich,  england, is considered 0 degrees longitude