Bismuth Bi Is Known to Be Radioactive.The Stability of

Multiple Choice

Bismuth
Bi is known to be radioactive.The stability of
Bi with respect to alpha,beta-plus and beta-minus decay is to be determined.The following atomic masses are known:
He: 4.002603 u
Tl: 207.981998 u
Pb: 211.991871 u
Bi: 211.991255 u
Po: 211.988842 u
The
Bi nucleus is

A) subject to alpha decay only.
B) subject to beta-plus decay only.
C) subject to beta-minus decay only.
D) subject to alpha or beta-plus decay,but not beta-minus decay.
E) subject to alpha or beta-minus decay,but not beta-plus decay.