Which doctrine did Brown v. Board reject?

Questions

Which dоctrine did Brоwn v. Bоаrd reject?

Exhibit 34-9   Cоuntry X Cоuntry Y Gоod A Good B Good A Good B 90 0 60 0 60 10 40 10 30 20 20 20 0 30 0 30 Refer to Exhibit 34-9. Which of the following stаtements is true?