A child holds a a 12.8 kg ball at a height of 3.3 m. The child then drop the balls, what is the kinetic energy just before the ball hits the ground?
414 )
42J
70
125 J

the answer is a for sure mark brainliest i had got this right on usatestprep

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.