Find the area of the shaded figureExpress result to the accuracy of 3 decimal.
Correct answers: 76
The first user who solved this task is Djordje Timotijevic.
Friedrich Adolf PanethDied 17 Sep 1958 at age 71 (born 31 Aug 1887). Austrian chemist who improved methods in the 1920's to isolate and measure the minute amounts of helium (as little as 10-10 cm3) slowly released by traces of radioactive elements in rocks. This enabled determination of both the age of rocks on earth, and also the age of meteorites which implies the age of the solar system, (presently accepted as 4,600 million years). Earlier, he and his friend Georg Charles de Hevesy introduced radioactive tracer techniques (1912-13). Paneth used radium D as a tracer to measure the solubility of lead salts, then extended the technique to the study of the unstable hydrides of lead and bismuth. He contributed to the study of the stratosphere by determining its composition as a function of altitude up to 45 miles.«