b$.$ Find the break$-$even points and determine the range of demand for which each location has a cost advantage. Do not round intermediate calculations. Round your answers to the nearest whole number. If the break$-$even point is negative, enter "DNE".

$\backslash$table$[[$Locations$,\backslash$table$[[$Break$-$even point$],[($units$)]],\backslash$table$[[$At $Q$ less than the$],[$break$-$even point,$],[$which location has$],[$a cost advantage?$]],\backslash$table$[[$At Q more than the$],[$break$-$even point,$],[$which location has$],[$a cost advantage?$]]],[$Philadelphia $-$ Atlanta,,$-$Select$-,-$Select$-],[$Philadelphia $-$ Miami,,$-$Select$-,-$Select$-],[$Philadelphia $-$ Houston,,$-$Select$-,-$Select$-],[$Atlanta $-$ Miami,,$-$ Select$-vv,-$ Select$-vv$