Determine whether or not each combination of substances can be used to create a buffer. 0.05 M HNO2, 0.05 M NaNO2 Buffer 1 M Na2HPO4, 1 M NaH2PO4 Not a buffer 0.1 M NH4Cl, 0.1 M HCl Not a buffer 0.4 M KOH, 0.2 M NaOH Not a buffer 0.1 M HCl, 0.1 M KCl

where are the choice options?

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.