Briefly trace the history of the atomic clock from 1940 until 1991.

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Explanation:

1945 — Isidor Rabi, a physics professor at Columbia University, suggests a clock could be made from a technique he developed in the 1930’s called atomic beam magnetic resonance. 1949 — Using Rabi’s technique, NIST (then the National Bureau of Standards) announces the world’s first atomic clock using the ammonia molecule as the source of vibrations.

your mothers brothers brother in law would be your father.

to demand women’s suffrage