Microscopy. numerical aperture.
Why Is It Called “Rock n’ Roll”?Is “Rocket ‘88” by Jackie Brenston and his Delta Cats the very first rock and roll record? The question has inspired debate among musicologists for years. Another equally contentious question: Where does the term rock and roll come from? Rock is derived from the Old English roccain, related to the Old Nordic rykkja meaning, “to pull, tear, move.” The earliest recorded use of the term in literature …
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