If the disintegration constant is $6.93 \times 10^{-6} \ s^{-1}$,then the half-life of $_{6}C^{14}$ will be:

The decay of $_{92}U^{235}$ is a reaction of .......... order.

The half-life of a radioactive isotope is $3 \ hours$. If the initial mass of the isotope were $256 \ g$,the mass of it remaining undecayed after $18 \ hours$ would be ....... $g$. (in $.0$)

The number of $\alpha$-particles emitted per second by a radioactive element falls to $1/32$ of its original value in $50 \ days$. The half-life period of this element is .......... $days$.

Radioactive lead $_{82}Pb^{201}$ has a half-life of $8 \ hours$. Starting from $1 \ mg$ of this isotope,how much will remain after $24 \ hours$?

What is the value of the decay constant of a compound having a half-life time $T_{1/2} = 2.95 \text{ days}$?