Answer :
A fixed cost of $100,100 will not change. At 3 units per output at $5555 the cost per unit would be 5555 divided by 3 which equals 1851.66 per unit. When increased to 4 Units per week the Fixed cost will remain the same the variable cost should be 4 times 1851.66 per unit which would equal $7406.66. So we can either conclude that the variable cost increases per unit or that the question is false!