What happened in 150 BC?

Explanation:

Seleucid Empire

The pretender to the Seleucid throne, Alexander Balas, who claims to be the son of the late Antiochus IV, defeats the Seleucid king, Demetrius I Soter, in battle and kills him. ... The new king of the Seleucid Empire, Alexander Balas, marries Cleopatra Thea, a daughter of Ptolemy VI Philometor of Egypt.

alaxander balas defeats his "father" and claims the throne of the Seleucid Empire

Explanation:

it provided for selection of government employees through competitive examinations. it also made it unlawful to fire or demote covered employees for political reasons or to require them to give political service or payment, and it set up a civil service commission to enforce the law.

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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