Determine the number of cartons sales of V1, V2 and V3 which will optimise profit for the firm, given the constraints of the following problem: Karl's Kitchens is experimenting with different vinegars for sale on the domestic market. The contribution margins per carton for three types (cleverly called V1, V2 and V3) are $120, $100 and $150 respectively. The firm is constrained in terms of labour hours, and the labour hours required per carton of each type of vinegar is 2 hours, 1.5 hours and 3 hours respectively. Assume the firm has 2,240 available labour hours per month, and the monthly demand is 1,200 cartons of V1, 800 cartons of V2 and 300 cartons of V3.