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Calculate the number 2487

NUMBERMANIA: Calculate the number 2487 using numbers [9, 6, 2, 4, 74, 153] and basic arithmetic operations (+, -, *, /). Each of the numbers can be used only once.

Correct answers: 28

The first user who solved this task is Fazil Hashim.

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Physical Exam

The doctor has just finished giving the young man a thorough physical examination.

"The best thing for you to do," the M.D. said, "is give up drinking and smoking, get to bed early and stay away from women."

"Doc, I don't deserve the best," said the patient. "What's second best?"

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First use of chemical symbols in British textbook.

In 1832, Edward Turner wrote a Preface to the 4th edition of his textbook, Elements of Chemistry (published 1833), in which he explained his use of symbols to represent reactants and products in a chemical reaction of Cyanogen, because he found they solved the difficulty of giving a “clear and concise description of. the phenomena in ordinary language.” His was the first use of chemical symbols in a British chemistry textbook. Turner used some algebra-type notation as suggested by William Whewell with parts of Jöns Jacob Berzelius's system, in which iron was represented by Fe (from Ferrum) and oxygen by O. Thus Fe + O represented one oxide of iron, and 2Fe + 3O represented another. Dots over the symbol indicated degree of oxidation, and an underline stood for two equivalents of a substance.«

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