A$.$ Polonium$-214$ has a half$-$life of $164$ s$.$ In $1$ ms$,$ how many half$-$lives will have passed? B$.$ If we start with $10,000$ atoms of Polonium, how many will we have left at the end of $1$ ms$?$ C$.$ If each Polonium$-214$ decay occurs by the emission of a $5$ MeV alpha particle, what is the total energy released via all the alpha particles in $1$ ms$?$ Give your answer in MeV. $($Hint: What you calculated in Part B is the number of atoms remaining, not the number of atoms that decayed.$)$ D$.$ If the biologically safe amount of energy absorption is $25$ MeV per minute, is Polonium safe to be around? a$.$ Yes b$.$ No