Which process is a source of outdoor air pollution? O releasing mold particles from an air conditioning vent
O emitting particles from a dump truck
O releasing radon gas from a generator
O emitting carbon monoxide from a heater

the answer is c.the valence of the atoms combine .

answerleaving cheese out to get moldy;

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.