- Imagine that you are holding a lead weight on the palm of
your hand. If the weight of
the lead is 0.80 N and the
bottom of the weight has an
area of 0.016 m2, what is the
pressure on the palm of your
hand?

it should be all of them because it asks if you included all of those in your answer

explanation:

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.