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Nasrin 24 T

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12. Nílton Corrêa De Sousa 3213
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last 3 solved tasks
If 678b4 + 6ac76 = ac9a30 find number abc. Multiple solutions may exist.
The computer chose a secret code (sequence of 4 digits from 1 to 6). Your goal is to find that code. Black circles indicate the number of hits on the right spot. White circles indicate the number of hits on the wrong spot.
If 3a131 - c0c6c = 1486b find number abc. Multiple solutions may exist.

Armand-Hippolyte-Louis Fizeau

Died 18 Sep 1896 at age 76 (born 23 Sep 1819). French physicist who was the first to measure the speed of light successfully without using astronomical calculations (1849). Fizeau sent a narrow beam of light between gear teeth on the edge of a rotating wheel. The beam then traveled to a mirror 8 km/5 mi away and returned to the wheel where, if the spin were fast enough, a tooth would block the light. Knowing this time from the rotational speed of the wheel, and the mirror's distance, Fizeau directly measured the speed of light. He also found that light travels faster in air than in water, which confirmed the wave theory of light, and that the motion of a star affects the position of the lines in its spectrum. With Jean Foucault, he proved the wave nature of the Sun's heat rays by showing their interference (1847).

April Fool's Day - Kid’s Socks

Sew one of your kid’s socks closed halfway down. If you’re the sewing type this prank will leave you in stitches.
Jokes of the day - Daily updated jokes. New jokes every day.
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