Задача 20561.

Find the number of molecules of helium in the volume of 1 cm ^ 3, the speed of which lie in the range from 2.41 to 2.43 km / s. Helium temperature 700 degrees Celsius, the density of 2.16 × 10 -4 kg / m ^ 3.

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.
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