Concept:Check which total cannot be made by adding some or all of the given box weights, using each box at most once.Explanation:Test the given totals using suitable combinations.210=20+90+40+60170=20+90+60190=90+40+60The remaining option is 200.No combination of 20, 90, 40, and 60 gives 200.Answer:200 kilograms cannot be the total weight.