In a student’s diet a meal consists of beefburgers and chips. Beefburgers have 1 unit of nutrient N1, 4 units of N2 and 125 calories per ounce. The figures for chips are 1/2 unit of N1, 1 unit of N2 and 60 calories per ounce. In the interests of the student’s health it is essential for the meal to contain at least 7 units of N1 and 22 units of N2. What should the student ask for on the next visit to the refectory to satisfy the nutrient requirements and minimise the number of calories?