Questions in nuclei

Select	Question
	Half life of $B{i^{210}}$ is 5 days. If we start with 50,000 atoms of this isotope, the number of atoms left over after 10 days is
	A nucleus of atomic mass A and atomic number Z emits ${M_1}$ particles. The atomic mass and atomic number of the resulting nucleus are
	The radioactivity of a certain radioactive element drops to 1/64 of its initial value in 30 seconds. Its half life is
	Radioactivity was discovered by
	The decay constant $\lambda $ of the radioactive sample is the probability of decay of an atom in unit time, then
	The average life T and the decay constant $\lambda$ of a radioactive nucleus are related as
	If T is the half life of a radioactive material, then the fraction that would remain after a time $\frac{T}{2}$ is
	If the decay or disintegration constant of a radioactive substance is $\gamma$, then its half life and mean life are respectively (log_e 2 can be written as ln 2)
	Which of the following is in the increasing order for penetrating power
	The half life of a radioactive element which has only $\frac{1}{{32}}$ of its original mass left after a lapse of 60 days is