Which tactic did Martin Luther King Jr employ to great effort in the civil rights movement

He used peace.

Explanation:

he did friendly and unarmed protests and speeches unlike malcolm x

- 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."

< 3