Answer
See answers.
Work Step by Step
Use mass and charge conservation to deduce the missing component(s) in the nuclear reaction.
a. Scandium-45 is the missing nucleus.
$$^{45}_{20}Ca\rightarrow\;^{45}_{21}Sc +e^-+\overline{\nu}$$
b. Copper-58 is the missing nucleus. When the isotope decays by $\gamma$ emission, the resulting nuclide is the exact same isotope, but in a lower energy state.
$$^{58}_{29}Cu^*\rightarrow\;^{58}_{29}Cu +\gamma$$
c. The positron and the neutrino are the missing particles.
$$^{46}_{24}Cr\rightarrow\;^{46}_{23}V +e^+ +\nu$$
d. Uranium-230 is the missing nucleus.
$$^{234}_{94}Pu\rightarrow\;^{230}_{92}U +\alpha$$
e. The electron and the antineutrino are the missing particles.
$$^{239}_{93}Np\rightarrow\;^{239}_{94}Pu +e^-+\overline{\nu}$$
