For the radioactive nuclei that undergo either `alpha or beta` decay, which one of the following cannot occur?

In ._92U^(238) radioactive series by alpha decay or beta decay, which one of the following can be the end product: Pb^(206),Pb^(207),Pb^(208),Pb^(209) ?

In radioactive decay, which one of the following moves the fastest ?

In beta -decay, the nuclei emit

The nuclide X undergoes alpha -decay and another nuclides Y undergoes beta^(ɵ) -decay, which of the following statement "is"//"are" correct?

The nuclide X undergoes alpha -decay and another nuclides Y undergoes beta^(ɵ) -decay, which of the following statement "is"//"are" correct?

Radioactive nuclei are being generated at a constant rate by some kind of nuclear reaction. If the decay constant for the radioactive nuclei is lambda , which of the following graphical representation is correct ? (initially, there are no radioactive nuclei present )

Radioactive nuclei are being generated at a constant rate by some kind of nuclear reaction. If the decay constant for the radioactive nuclei is lambda , which of the following graphical representation is correct ? (initially, there are no radioactive nuclei present )

A radioactive element X has an atomic number of 100. It decays directly into an element Y which decays directly into an element Z . In both the processes either one alpha or one beta- particle is emitted. Which of the following statement could be true?