Human Resources - Independent Contractors, Discriminatory Practices, Class Groups

Please help with the following questions. Detail answers and examples would be greatly appreciated.

1. When using independent contractors, firms must be prepared to relinquish most of their control over how the work is done. Why is this good advice? Include an example in your answer.

2. Employment requirements and practices should be scrutinized for their potential to disadvantage protected class groups and for evidence of their job relatedness and business necessity. Is this good advice? Why or why not? What kind of discrimination would this be evidence of? What should the employer do if scrutiny turns up evidence of discriminatory practices?