What are the causes of economic disparities or representational disparities between and among racial and ethnic groups in society?

Question: What are the causes of economic disparities or representational disparities between and among racial and ethnic groups in society? Is it only because of negative discrimination (based on race/ethnicity)? What are the other relevant factors discussed by Thomas Sowell and/or Walter Williams? What, if anything, should our American federal or state governments do about economic disparities or representational disparities between and among racial groups in society? Why?

For your essay, you must discuss the arguments and evidence covered in the Required Sources:

Thomas Sowell, Discrimination and Disparities,Chapter 5 or Thomas Sowell, Civil Rights: Rhetoric or Reality? Chapter 6 or Epilogue