Solve for the missing amounts for the following separate cases.

$\backslash$table$[[$Case darr,$\backslash$table$[[$Sales price$],[$per unit$]],\backslash$table$[[$Variable costs$],[$per unit$]],\backslash$table$[[$Total$],[$Fixed costs$]],\backslash$table$[[$Break$-$even$],[$in units$]]],[1,20,16,40,000,],[2,25,5,,5,000],[3,30,,81,000,9,000],[4,40,4,48,000,8,000]]$