Answer
The nuclides that are doubly magic are: $^{132}Sn$, $^{208}Pb$
Work Step by Step
$Z$ is the number of protons in a nucleus
$N$ is the number of neutrons in a nucleus
The magic nucleon numbers are 2, 8, 20, 28, 50, 82, and 126.
If $Z$ or $N$ (or both) equal a magic number, then the nuclide is said to be magic.
If both $Z$ and $N$ equal a magic number, then the nuclide is said to be doubly magic.
We can find the value of $Z$ and $N$ for each nuclide.
$^{122}Sn$
$Z = 50$
$N = 72$
$^{132}Sn$
$Z = 50$
$N = 82$
$^{98}Cd$
$Z = 48$
$N = 50$
$^{198}Au$
$Z = 79$
$N = 119$
$^{208}Pb$
$Z = 82$
$N = 126$
The nuclides that are doubly magic are: $^{132}Sn$, $^{208}Pb$
