The radioactive isotope i-131 is used in
a) geologic dating
b) controlling speeds of neutrons
c) controlling fission reactions
d) medical diagnosis

d.) circle motion requires a force to give it a centripetal acceleration.

some sources quote the lethal dose, for an average 170lbs opiate-naive individual is between 75 and 375 mg

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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