Who was the plaintiff in the Supreme Court decision that upheld the legal doctrine of separate but equal

The correct answer is Homer Adolph Plessy

Explanation: Homer Adolph Plessy  was an American creole shoemaker and insurance broker who became notable for being the plaintiff in the case of the United States Supreme Court known as Plessy v. Ferguson.

what are local authorities doing to fix the problem

explanation:

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

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