Identify the unknown isotope (mathrm{X}) in the following decays. a. (mathrm{X} ightarrow{ }^{224} mathrm{Ra}+alpha) b. (mathrm{X}

Identify the unknown isotope \(\mathrm{X}\) in the following decays.

a. \(\mathrm{X} \rightarrow{ }^{224} \mathrm{Ra}+\alpha\)

b. \(\mathrm{X} \rightarrow{ }^{207} \mathrm{~Pb}+\mathrm{e}^{-}\)

c. \({ }^{7} \mathrm{Be}+\mathrm{e}^{-} \rightarrow \mathrm{X}\)

d. \(\mathrm{X} \rightarrow{ }^{60} \mathrm{Ni}+\gamma\)