Carbon-11 is a radioactive isotope of carbon. Its half-life is 20 minutes. What fraction of the initial number of C-11 atoms in a sample will remain after 80 minutes?

iron and sleel

make siroeel

the answer is 75.0%.

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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