Which of the following supports the argument that the president is free to exercise command and ...

Which of the following supports the argument that the president is free to exercise command and authority over the executive branch in all respects?
 
  a. the take care clause
  b. the vesting clause
  c. the theory executive privilege
  d. the theory of unitary executive

Question -2-

The Civil Rights Act of 1964 and the Voting Rights Act of 1965 served as the final nails in the infamous separate but equal doctrine, articulated in which of the following Supreme Court cases?
 
  a. Plessy v. Ferguson
  b. Dred Scott v. Sanford
  c. Brown v. Board of Education
  d. Marbury v. Madison