A hypothetical atom has two energy levels, with a transition wavelength between them of $580$ nm$.$ In a particular sample at $300$ K$,4\mathrm{.}01020$ such atoms are in the state of lower energy. $($a$)$ How many atoms are in the upper state, assuming conditions of thermal equilibrium? $($b$)$ Suppose, instead, that $3\mathrm{.}01020$ of these atoms are $$pumped$$ into the upper state by an external process, with $1\mathrm{.}01020$ atoms remaining in the lower state. What is the maximum energy that could be released by the atoms in a single laser pulse if each atom jumps once between those two states $($either via absorption or via stimulated emission$)?$