An electrically neutral atom of gallium has 31 electrons and 39 neutrons. what is the mass number of the atom?

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.

it’s previous models   because when i picked that son of a gun’s answer it was wrong look for previous models because they might make it a different letter  

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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