There are two chemical systems, $A$ and $B$, each with two particles that have a total energy of $20 \mathrm{~J}$. For the first system, the two particles each can have energies of 0,5 , $10,15,$ or $20 \mathrm{~J},$ and for the second system, the particles can have energies of $0,10,$ or $20 \mathrm{~J}$. Which configuration will have the least entropy?