The electron emitted in beta radiation originates from

$A$ nucleus $X$ emits a beta particle to produce a nucleus $Y$. If their atomic masses are $M_{x}$ and $M_{y}$ respectively, the maximum energy of the beta particle emitted is (where $m_{e}$ is the mass of an electron and $c$ is the velocity of light):

Assertion: ${}^{90}Sr$ from the radioactive fallout of a nuclear bomb ends up in the bones of human beings through the milk consumed by them. It causes impairment of the production of red blood cells.
Reason: The energetic $\beta$-particles emitted in the decay of ${}^{90}Sr$ damage the bone marrow.

$A$ certain radioactive material $_ZX^A$ starts emitting $\alpha$ and $\beta$ particles successively such that the end product is $_{Z-3}Y^{A-8}$. The number of $\beta$ and $\alpha$ particles emitted are

$A$ certain radioactive material can undergo three different types of decay,each with a different decay constant $\lambda_1$,$\lambda_2$,and $\lambda_3$. Then the effective decay constant is:

Pauli suggested the emission of neutrino during $\beta^{+}$ decay to explain: