The landmark civil rights case of "brown v. board of education" rendered invalid the decision in which supreme court case? a."board of regents of california v. bakke" b."plessy v. ferguson" c."roe v. wade" d."mcculloch v. maryland"

What was zheng he’s most important accomplishment? zheng he spread chinese ideas and brought wealth to china from his travels. zheng he commanded an impressive fleet of ships. zheng he sailed the indian ocean and around africa. zheng he conquered lands as far away as africa to increase the dynasty’s power.